TW201520586A - Anti-reflection article and methods thereof - Google Patents

Abstract

An antireflection article including: a transparent substrate having a refractive index of from 1.48 to 1.53; a binder layer associated with the substrate, the binder having a refractive index of from 1.55 to 1.75; and a nanoparticulate monolayer or near monolayer associated with the binder layer, the nanoparticulate layer having an effective refractive index less than the refractive index of binder. Methods of making and using the article are also disclosed.

Description

Anti-reflective article and method of manufacturing the same

The present application claims priority to U.S. Application Serial No. 61/872,037, filed on Aug. 30, 2013, the content of which is hereby incorporated by reference.

Cross-references to related applications

The present disclosure is related to commonly owned and assigned USSN 13/440183, filed on Apr. 5, 2012, and issued to US 2012-0281292; USSN 61/557490, now USSN 13/668537, filed November 2012 5th; USSN 61/731924, application on November 30, 2012; USSN 13/090561, application on April 20, 2011; USSN 13/662789, application on October 29, 2012; USSN 13/900659, The application is filed on May 23, 2013; and USSN 61/872043, filed on Aug. 30, 2013, the entire disclosure of each of which is hereby incorporated by reference in its entirety in its entirety herein.

The present disclosure is generally directed to anti-reflective (AR) surfaces, articles having such surfaces, and methods of making and using the same.

There are still many shortcomings in the prior art. The present invention is directed to solving such disadvantages and/or providing improvements over the prior art.

In an embodiment, the present disclosure provides an anti-reflective (AR) coating having at least one layer comprising a single layer or a nearly monolayer of nanoparticle.

In an embodiment, the present disclosure provides an article incorporating an AR coating.

In an embodiment, the present disclosure provides a method of making an article, the method comprising the steps of: depositing a binder on a substrate; and depositing a single layer or a near monolayer of nanoparticle on the binder.

In an embodiment, the present disclosure provides a method of using an article, such as in a display device, the method comprising the steps of incorporating the disclosed article in a display device.

100‧‧‧AR objects

110‧‧‧Substrate

120‧‧‧Binder layer

130‧‧‧Nano particle single layer

500‧‧‧ surface

510‧‧‧ another particle coated surface

600‧‧‧ curve

610‧‧‧ Curve

800‧‧‧ objects

810‧‧‧ glass substrate

820‧‧‧High refractive index layer / relatively high refractive index adhesive layer

830‧‧・Nano particle single layer

D‧‧‧Nanoparticle diameter/nanoparticle average diameter/average diameter/ball diameter/diameter/nanoparticle sphere diameter/nanoparticle nominal diameter

g‧‧‧The distance the particles sink into the adhesive layer

n _g ‧‧‧Adhesive layer refractive index / refractive index

n _p ‧‧‧particle refractive index / refractive index

n _s ‧‧‧Substrate refractive index / refractive index

P‧‧‧pitch/average nanoparticle spacing/average spacing

In an embodiment of the present disclosure: Figure 1 shows an AR article having a multi-layered AR surface having a single layer of nanoparticle particles in a closely packed arrangement.

2A and 2B show views of an exemplary AR article having a multilayer AR coating (2A is a side view, 2B is a top view), the multilayer AR coating comprising nanoparticles having nanoparticles in a non-close packed hexagonal arrangement Single layer of particles.

Figure 3 shows a graphical representation of coating performance for various pitch/diameter ratios or values and high refractive index layer thickness normalized to a particle diameter for a high refractive index value of 1.6.

Figures 4A and 4B show examples of reflective spectra taken from the preferred design space of Figure 3.

Figure 5 shows an example of a preferred design structure (with 100 nm particles) providing 100 nm particles deposited directly on the substrate (the particles have a refractive index (n _p ) of, for example, 1.51) (no second layer; 500) and Figure 4 And having a comparison of the second intermediate binder layer; 510).

Figures 6A and 6B show graphs providing a comparison of spectral width versus angle of incidence (AOI) for the two examples shown in Figure 5.

Figures 7A through 7E provide exemplary spectra of some values of a high refractive index ( _ng ) layer having a refractive index of 1.55 (Fig. 7A) to 1.75 (Fig. 7E).

Figure 8 provides a schematic illustration of another article (800) having a glass substrate (810) and a nanoparticle monolayer (830) partially submerged or immersed in a high refractive index layer (820).

Figures 9A and 9B show exemplary spectra of the design structure in which the nanospheres of the nanoparticle single layer are partially immersed in the high refractive index layer.

Various embodiments of the present disclosure are detailed with reference to the drawings, if any. The scope of the present invention is not limited by the scope of the invention, and the scope of the invention is limited only by the scope of the appended claims. In addition, any examples set forth in this specification are not limiting, and only some of the many possible embodiments of the claimed invention are set forth.

definition

"Anti-reflection" and like terms mean a reduction in total reflection (specular reflection and diffuse reflection) which can be induced by coating or surface treatment.

"Adhesive", "adhesive layer" and like terms mean a material that can be used to bond surfaces or between reinforcing surfaces, such as between particles or between particles and glass surfaces.

"Nanoparticle monolayer" and like terms mean a single layer of particles that are typically in contact with a surface or substrate, wherein the particles have an average or average diameter of substantially less than about 500 nm or less, and most of the particles have less than about Or negative (+/-) 100% size change. The spacing between the particles is preferably substantially uniform.

"Near-monolayer" and like terms mean a nanoparticle monolayer as defined above having a plurality of defective regions, such as incomplete surface coverage, or a two-layer stack of particles, or between particles Irregular intervals. Usually such defective areas will account for no more than 50% of the total area of the single layer.

"Associate" and similar terms refer to the relationship of the binder layer to the substrate, the relationship of the nanoparticles to the substrate, or both, which may include, for example, physical contact, such as Physical interactions of mechanical interlocks, chemical bonding interactions, and similar interactions or combinations thereof.

"Effective refractive index" and like terms mean the average refractive index measured by a nanostructured material or coating, which may be a known optical method such as ellipsometry or enthalpy coupling. To measure, the effective refractive index measured is some superposition of the refractive indices of individual materials (such as glass and air) that form the individual nano-domains of the nanostructure. Since the nanostructured material has characteristics that are smaller than the wavelength of visible light, the measured refractive index is regarded as the effective refractive index.

"Reflective" and similar terms mean, for example, covering 400 nm to The object has an average reflectivity of less than 0.1% to 0.2% with respect to a single surface or side of the article over a spectral width of at least 100 nm of at least a portion of the visible wavelength spectrum of 700 nm.

"Second binder between the nanoparticle monolayer and the binder" and similar terms or phrase means, for example, between nanoparticles, between nanoparticles and binder layers, nanoparticles and Bonding between coatings, between particles and substrates, or combinations thereof, such as adhesive interactions, chemical interactions or bond-like interactions.

"include", "includes" or similar terms are meant to cover, but not limited to, inclusion and non-exclusive.

"About" modifications are used to describe, for example, the amounts, concentrations, volumes, process temperatures, process times, yields, flow rates, pressures, and the like, and ranges thereof, in the compositions of the present disclosure. For example, variations in numerical quantities that may occur as a result of typical measurements and processing procedures for preparing materials, compositions, composites, concentrates, or using formulations; unintentional errors in such procedures Differences in the manufacture, source or purity of the starting materials or ingredients used to carry out the methods; and similar considerations. The term "about" also encompasses amounts that differ due to aging with a particular initial concentration or composition or formulation of the mixture, and that vary by mixing or treating a composition or formulation having a particular initial concentration or mixture.

"Consisting essentially of" in an embodiment may relate to, for example, an article having an anti-reflective surface as defined herein; a method of making or using an anti-reflective article as defined herein; or incorporating A display system for objects as defined herein.

The articles, display systems, methods of making, and using, compositions, formulations, or any devices of the present disclosure may include the components/components or steps recited in the claims, and compositions that do not substantially affect the present disclosure. Other components/components or steps of the basic and novel nature of the articles, equipment, or methods of making and using, such as specific reactants, specific additives or ingredients, specific reagents, specific surface modifiers or conditions, or similar Structure, material or process variable. Items that may substantially affect the essential properties of the components/components or steps of the present disclosure or that may impart undesirable features to the present disclosure include, for example, surfaces having undesirably highly reflective properties that are beyond the scope of this document. Defined and specified values, including intermediate values and ranges.

The indefinite article "a" or "an" and "the"

Abbreviations well known to those skilled in the art can be used (for example, hour or hour is abbreviated as "h" or "hr", milliliter is abbreviated as "mL", and room temperature is abbreviated as "rt", and nanometer abbreviation is " Nm" and similar abbreviations).

The specific and preferred values and their ranges for the components, ingredients, additives and the like are disclosed for illustrative purposes only; the values and their ranges do not exclude other defined values or others within the defined ranges. value. The compositions, devices, and methods of the present disclosure can include any value or any combination of the values, specific values, specific values, and preferred values described herein.

Anti-reflective (AR) coatings have been utilized for decades. Recent research efforts have focused on the fabrication of anti-reflective coatings composed of a single layer of nanoparticle on a substrate. Such nanoparticle monolayers can have unique combinations of features such as: low reflection; Higher durability compared to nanoporous coatings with equal effective refractive indices; easy ion-exchange strengthening of glass substrates coated with nanoparticle monolayers; compared to multilayer high-low refractive index AR coatings Lower effective fingerprint visibility; wide reflection bandwidth, and low angle sensitivity of refraction. Examples of such recent AR coatings and related fabrication methods are described in the above-referenced co-owned and assigned application.

For a given size and spacing of nanoparticles in a single layer, it would be beneficial to have a method of reducing the minimum reflection, broadening the wavelength band of the low reflection of the AR coating, or both.

In an embodiment, the present disclosure provides an anti-reflective article comprising: a transparent substrate having a refractive index (n _s ) of 1.48 to 1.53; a binder layer (ie, a coating composition) bonded to the substrate, the bonding agent having a relatively high refractive index of about 1.55 to about 1.75 (n _g), the adhesive layer, the refractive index (n _g) is greater than the refractive index of the transparent (n _s) (i.e. n _g> n _s) of the substrate; and The binder layer is combined with a single layer or a nearly monolayer of nanoparticle, the nanoparticle layer having an effective refractive index (n _{p eff} ) (ie, n _g >n _{p eff} ) smaller than the refractive index of the binder layer, such as less than 1.55 n _{p eff} .

In an embodiment, the effective refractive index (n _{p eff} ) of the nanoparticle monolayer may be, for example, 1.1 to 1.5, 1.15 to 1.3, and the like, including intermediate values and ranges.

In an embodiment, the antireflective reflectance of the article may have an average reflectivity of, for example, less than 0.2% over a spectral width of at least 100 nm covering at least a portion of the visible wavelength spectrum of 400 nm to 700 nm.

In an embodiment, the nanoparticle monolayer may comprise, for example, nanoparticles in a non-close packed hexagonal geometry having 1.05 to The spacing (p) of 1.35, and preferably 1.15 to 1.25 (including intermediate values and ranges) (i.e., the separation distance between the centers of adjacent nanoparticles) and the nanoparticle diameter (D) ratio (p/D).

In an embodiment, the binder may have a thickness of, for example, 1 x D to 2 x D, and preferably from 1.3 x D to 1.8 x D, including intermediate values and ranges, where D is the average diameter (D) of the nanoparticle.

In an embodiment, the transparent substrate can be, for example, glass, polymer, glass-ceramic, crystalline oxide, semiconductor, and the like, or a combination thereof.

In an embodiment, the anti-reflective article may further comprise, for example, a second binder between the nanoparticle monolayer and the binder.

In an embodiment, the nanoparticle monolayer may have, for example, 85% to 100%, 90% to 93% of the nanoparticle surface coverage and similar surface coverage, including intermediate values and ranges, and the nanoparticle near monolayer A monolayer of nanoparticles substantially including, for example, nanoparticle surface coverage of 50% to 90%, 65% to 90%, and similar surface coverage (including intermediate values and ranges) may be included. This surface area coverage is performed using standard microscopy including electron microscopy and by projecting the visible profile of the nanoparticle onto the surface of the substrate (eg, by calculating the visible view of the particle (see The percentage of the microscopic surface image of the coverage area is measured by the percentage of the substrate visible as the uncovered area.

In an embodiment, the nanoparticulate layer may comprise, for example, at least one of the following nanoparticulates: vermiculite, alumina, zirconia, polystyrene, latex, and the like, or combinations thereof.

In an embodiment, the nanoparticle monolayer may comprise, for example, an average diameter (D) having a thickness of 50 nm to 300 nm and having a geometry selected from at least one of the following: Nanoparticles: spheres, hemispheres, ellipsoids, disks, cones, cylinders, columns and similar shapes and geometries or combinations thereof.

In an embodiment, the nanoparticle monolayer combined with the binder may comprise, for example, nanoparticles on the surface of the binder; partially embedded or partially immersed in the binder; completely covered by the binder or Completely immersed in the binder, or a combination thereof.

In an embodiment, the nanoparticle monolayer bonded to the binder may, for example, be partially embedded in the binder up to 0.1 x D to 0.5 x D, where D is the average diameter (D) of the nanoparticle.

In an embodiment, the adhesive layer on the substrate can have a thickness of, for example, 60 nm to 300 nm, including intermediate values and ranges.

In an embodiment, the binder may comprise, for example, a polymer; a nanoparticle filler material such as a polymer or sol-gel matrix filled with vermiculite nanoparticles having a diameter of 10 nm; an inorganic oxide material; an inorganic nitride Materials; semiconductors; transparent conductors and similar materials or combinations thereof.

In embodiments, the binder may further comprise at least one of the following particles or salts: a compound of silver, copper, silver or copper, or a combination thereof, which may provide, for example, an antimicrobial benefit.

In an embodiment, the present disclosure provides a method of making the aforementioned anti-reflective article, the method comprising the steps of: depositing a layer of adhesive on at least a portion of a substrate; and depositing a single layer or a near monolayer of nanoparticle on the binder On the floor.

In an embodiment, the fabrication method may further comprise, for example, the following steps: via, for example, curing, crosslinking, fusing, sintering, and the like, or In combination, a single layer of nanoparticle is immobilized on or in the adhesive layer.

In an embodiment, the fabrication method may further comprise, for example, the step of curing the adhesive layer before, during, after, or a combination thereof.

In an embodiment, the step of immobilizing or fusing the nanoparticle monolayer on the binder may comprise, for example, the following steps: thermal sintering; depositing a binder between the binder and the deposited nanoparticle monolayer; The binder is deposited on the combined first binder and the deposited nanoparticle monolayer; or a combination thereof.

In an embodiment, the method may further comprise, for example, the step of: chemically strengthening the object by ion exchange of at least one of: ion exchange of the substrate before depositing the binder; ion exchange of the binder on the substrate; and nanoparticle Ion exchange of the substrate before the monolayer is fixed on the binder; ion exchange of the substrate after deposition or after fixing the monolayer of nanoparticle, or a combination thereof.

In an embodiment, the present disclosure provides an article having a multilayer AR coating, wherein one of the layers consists of a single layer or a nearly monolayer of nanoparticle. Nanoparticles constituting a single layer or a nearly monolayer may have a size of, for example, 50 nm to 300 nm, including intermediate values and ranges. The single or near monolayer of nanoparticles can comprise, for example, nanospheres, nanohemispheres, and similar three-dimensional geometries.

In an embodiment, at least one adhesive layer having a relatively high refractive index layer having an effective refractive index higher than an effective refractive index of a single layer of nanoparticle may be disposed under a single layer of nanoparticle rate. The layer of adhesive underneath the nanoparticle can be used to reduce reflection or broaden the band of low reflection produced by the AR nanoparticle coating.

In an embodiment, the present disclosure provides optical modeling results that can be used, for example, to define a preferred range of thicknesses and refractive index ranges for adhesive layers combined with different nanoparticle monolayer configurations, and to imply manufacturing method. The adhesive layer can perform other functions as needed, such as self-cleaning functions (eg, using TiO ₂ materials), hydrophobic or oil repellency, or providing adhesion, adhesion, or easy to sinter surfaces of nanoparticles. As an example, antimicrobial benefits can be obtained when a compound of silver, copper, silver or copper, or a mixture thereof, is incorporated into the binder layer.

In an embodiment, the disclosed AR nanoparticle coating can provide a lower reflection at a particular wavelength, or a wider wavelength band with a lower reflection than a single nanoparticle monolayer on the surface.

In an embodiment, the present disclosure provides an anti-reflective article comprising: a transparent substrate having a first index of refraction (n _s ); a binder layer bonded to the substrate, the binder having a refractive index greater than the substrate (n _s a second refractive index (n _g ); and a single or near monolayer of nanoparticle bound to the binder layer, the nanoparticle monolayer or near monolayer having an effective refractive index less than the refractive index (n _s ) of the substrate Rate (n _{p eff} ).

In an embodiment, the reflectivity of the article has an average reflectivity of less than 0.2% over a spectral width of at least 100 nm covering at least a portion of the visible wavelength spectrum of 400 nm to 700 nm.

In an embodiment, the substrate refractive index n _s is about 1.4 to 1.55, the adhesive layer refractive index n _g is about 1.55 to 1.75, and the nanoparticle monolayer or near monolayer effective refractive index (n _{p eff} ) is about 1.15. To 1.4.

Referring to the drawings, Figure 1 shows an exemplary embodiment of an AR article (100) having a multilayer AR coating that incorporates a nanoparticle monolayer (130) into a coating. There is a substrate (110) having a relatively high refractive index adhesive layer (120).

In an embodiment, the single layer of nanoparticle may be, for example, a vermiculite nanosphere deposited on top of a coating of a high refractive index adhesive layer. Individual nanospheres may have a refractive index close to, for example, 1.45, but a substantial portion of the air, or the free space present within the nanoparticle monolayer or between individual nanoparticles, may result in a single layer of nanoparticle that may be, for example, 1.15 to Effective refractive index of 1.30 (n _{p eff} ). In an embodiment, the relatively high refractive index adhesive layer coating may comprise at least a portion of a top surface of a transparent substrate such as glass. The nanoparticles may be, for example, vermiculite nanoparticles having a diameter or size of 50 nm to 300 nm with a certain spacing between the centers of the particles. The spacing interval has a minimum value of D (the diameter of the 1 x nanoparticle) and a maximum value that is not specifically limited. Preferred values of the spacing spacing relative to the diameter are discussed further below. The spacing between the nanoparticle nanospheres need not be regular, however the spacing can be specified as the average spacing of the nanospheres over the area of (10λ _o ) ² , where λ _o is the central wavelength at which the desired AR performance is achieved. The variance of the spacing within the same area should be less than 5%.

The high refractive index of the adhesive layer in contact with the single layer of nanoparticle particles may have a refractive index (n _g ) of substantially 1.55 to 1.75, and the high refractive index layer may have a thickness of, for example, 60 nm to 300 nm to provide in the visible wavelength Good AR performance. A more detailed description of the preferred range of high refractive index adhesive layer thicknesses is provided below.

The transparent substrate can be, for example, glass or any other transparent substrate such as plastic. The calculated refractive index range of the preferred structure is generally effective for a transparent substrate having a refractive index (n _s ) of approximately 1.48 to 1.53 when the external ambient medium is air. However, the preferred structure can be modified to be suitable for substrates having a refractive index outside this range.

The multilayer geometry of the disclosed objects is modeled using effective medium theory. This model has been shown to have excellent agreement with the measured reflectance of the dip coated nanoparticle coating. The substrate refractive index (n _s ) is assumed to be 1.51 and the particle refractive index (n _p ) is 1.46 for various high refractive index adhesive layer thicknesses (0 to 100xD), refractive index (1.55 to 1.75), and pitch values (1xD to 1.3xD) to simulate reflectivity. The reflectance spectra were then evaluated using a measure of spectral breadth, flatness, and total reflectance at each thickness-refractive-pitch value.

2A and 2B show views of an exemplary AR article having a multilayer AR coating (2A is a side view; 2B is a top view), the multilayer AR coating comprising nanoparticles having nanoparticles in a non-close packed hexagonal arrangement Single layer of particles.

Figure 3 shows an illustration of coating performance for various pitch/diameter values and high refractive index adhesive layer thicknesses normalized to particle diameters for a high adhesion index value of 1.6. The shaded contour regions show the average reflectivity of the portion of the spectrum where the reflectivity is less than 0.5%; the darkest shading indicates a lower value. The black contour corresponds to a range of widths of the spectrum with a reflectivity below 0.5%; this spectral width is normalized to the particle diameter. The area marked with the oval line indicates a preferred design space or zone in which less than 0.5% reflectivity can be achieved in the range of about 2.5 x D and an average reflectance of less than 0.2% is achieved over this band. Reflective scales are shown on the right.

Fig. 3 is a diagram showing an example of the reflectivity of the relative pitch (p) and the thickness (g) of the adhesive layer in terms of the refractive index of the adhesive layer of 1.6. From this illustration, the skilled artisan can determine that preferred embodiments of the present disclosure are, for example, between about 1.15 and about 1.25/D, and a layer thickness (g) of 1 x D to 2 x D or 1.3 x D to 1.8 x D.

Figures 4A and 4B show examples of reflective spectra taken from the preferred design space of Figure 3. Figure 4A shows the spectrum for a sphere diameter (D) with an average nanoparticle spacing (p) equal to 1.2 times 1.2 nm and a high refractive index layer thickness of 1.6 times D. Figure 4B is the same solution, but for 100 nm diameter nanoparticles, where D is equal to 100 nm, this solution produces a low reflection band in the visible portion of the spectrum.

The reflectance spectrum of Fig. 4A has a pitch /D equal to 1.2, a refractive index (n _g ) equal to 1.6, and a thickness /D equal to 1.6. It is often desirable to obtain an AR coating having good performance at a visible light having a wavelength of, for example, be selected so that the person skill D is equal to 100nm, is equal to n _g 1.6, equal to the thickness of 160nm and is equal to the pitch of 1.2 / D to be used for this same The structure was designed such that an average reflectance of 0.14% from 450 nm to 650 nm was obtained. Table 1 lists the widths in this spectrum that fall below a given reflectance cutoff point.

For an intermediate binder layer having a high refractive index of 1.55 to 1.75, the average pitch (p) in a single layer of the vermiculite nanospheres may be, for example, between 1 x D and 1.3 x D, and preferably 1.15 x D to 1.25. xD. The thickness (t) of the high refractive index layer can be For example, 1xD to 2xD, and more preferably 1.3xD to 1.8xD. Low reflectivity performance can be achieved with a thicker intermediate binder layer, but the spectrum tends to be less flat for such thicker interlayer methods. However, a flat spectral response is usually more desirable. The diameter (D) of the spherical nanoparticle or nanosphere can be selected to achieve low reflection over the desired wavelength range. Exemplary preferred parameters for the refractive index of some high refractive index adhesive layers are given in Table 2.

Figure 5 shows a graph comparing the modeled reflectance spectra of the two particle coated surfaces. One surface (500) has 100 nm nanoparticles (e.g., vermiculite particles) that are deposited directly on the substrate without a binder layer. The particle coated surface without the binder layer has a refractive index of the substrate equal to 1.51. Having 100 nm nanoparticle (for example, the same vermiculite particle as in surface (500)) and a binder layer (ie, an intermediate binder layer having a high refractive index, SiO ₂ -TiO ₂ sol-gel blend) Another particle coated surface (510) is an example of a preferred design of Figure 4. The deposition of nanoparticle spheres on a high refractive index adhesive layer having a refractive index ( _ng ) equal to 1.6 broadens the low reflectivity portion of the spectrum and reduces overall reflectivity.

Figures 6A and 6B show graphs providing a comparison of spectral width versus angle of incidence (AOI) for the two examples shown in Figure 5. Figure 6A shows the graph A spectral width (in nm) of less than 0.5% reflectivity, wherein the curve (610) comprises a layer of adhesive and the curve (600) does not comprise a layer of adhesive. The graph of Figure 6B shows the same result for a 1% width reflective cutoff point, where curve (630) includes the adhesive layer and curve (620) does not include the adhesive layer. These results demonstrate that improved angular performance can be achieved by the disclosed objects and methods.

Figures 7A through 7E provide exemplary % reflectance spectra for some of the intermediate binder layer values listed in Table 3, with the intermediate binder layer having an increment of 1.55 (Fig. 7A) to 1.75 (Fig. 7E) Refractive index.

Figure 8 provides a schematic illustration of another exemplary article (800) having a glass substrate (810), a nanoparticle monolayer (830) that is submerged or immersed in a relatively high refractive index adhesive layer (820). in. To improve the hardness of the AR coating, as shown in Figure 8, it may be desirable to partially deposit the nanospheres into the adhesive layer. This can be accomplished, for example, by adding a layer of binder after depositing the sphere onto the surface, or the sphere can sink into the layer during, for example, a heat treatment step. In the case where the nanoparticles are partially sunk into the binder layer, it is possible to obtain a broad band and low reflectivity.

Figures 9A and 9B show exemplary spectra of low reflectivity structures in which the nanospheres are partially immersed in the adhesive layer. The sphere can be sunk by sinking as indicated by the diameter fraction given in the graph legend (right side). Curve diagram of Figure 9A The sinking particles are shown to cause the low reflectivity regions to shift to shorter wavelengths, and the reflective bandwidth normalized to the nanoparticle sphere diameter (D) is also reduced. The graph of Figure 9B shows the same result for the spectrum plotted for the low reflectivity nanoparticle sphere diameter (D) in the visible spectrum. Since the larger the sinking, the larger the diameter required, the actual bandwidth of the low-reflectivity region increases slightly as the nanoparticle sinks. The diameter used (in nm) is given together with the sinking fraction (right side) in the legend. All of the simulations shown in Figures 9A and 9B used an intermediate binder layer having a refractive index of 1.6. The other numbers of these spectra are given in Table 4.

The specific parameters are taken from another preferred design space for the level of each layer of particle sinking: where t/D is the ratio of the thickness of the adhesive layer (t) to the diameter of the particles (D); g/D is such as a sphere The nanoparticle is a sinking amount of the sphere diameter, where g is the distance the particle sinks into the binder layer, D is the nominal diameter of the nanoparticle; p is the spacing; "0.5% wid" is The reflectance is less than 0.5% of the spectral width; and "Ave Refl" refers to the average reflectance of the spectrum below 0.5% reflectivity.

As shown by the spectrum of Figure 9, the desirable AR performance can be achieved with sinking of the nanospheres from 0 to 0.33 x D, and even up to 0.5 x D. Sinking the particles into the high-refractive-index adhesive layer does slightly change the design space. In the meantime, and for a given particle diameter, for example, the low reflectivity region shifts to a shorter wavelength due to an increase in the sinking fraction. Referring again to Figure 9A, it is necessary to increase the diameter of the nanosphere as the sinking fraction increases to maintain low reflectivity in the same wavelength band. In this case, although the larger sinking score is slightly inclined to a larger bandwidth, the spectral bandwidth remains largely unchanged.

The manufacturing method of the present disclosure is not particularly limited. In embodiments, the adhesive layer coating can be deposited on a transparent substrate by any of a variety of film coating methods known in the art, including, for example, thermal evaporation, electron beam evaporation, DC sputtering. Plating, reactive AC sputtering, CVD, liquid based sol-gel or polymer coating, spin coating, dip coating, spray coating, slot/slot coating, roll coating, and similar coating methods, or combinations thereof. The material of the adhesive layer as the adhesive layer coating layer may include, for example, a polymer such as an acrylate polymer, a polyester, a polyimide, a nanoparticle filling material, and an inorganic substance such as SiO ₂ -TiO ₂ blending. , SiOx-SiNy blend (see, for example, Nanoscale Research Letters , February 2012, 7:124), Al ₂ O ₃ , such as AlOxNy, SiAlxOyNz, Si3N4, TiN, TiNwOv (see, for example, US Patent Application Publication No. 2011) /0020638) nitrides and nitrogen oxides and similar materials or combinations thereof.

In an embodiment, the adhesive layer may be formed, for example, of a SiO ₂ -TiO ₂ sol-gel blend tailored to have a refractive index of 1.60 and a thickness (t) of from 100 nm to 150 nm. The sol-gel adhesive layer or coating can be prepared by, for example, dip coating, spin coating, spray coating or the like, and then cured at 150 ° C to 550 ° C. Subsequently, the nanoparticles can be deposited in a single layer on top of the SiO ₂ -TiO ₂ layer. The nanoparticle monolayer can be deposited from an aqueous suspension or a solvent based suspension using, for example, dip coating, spin coating, spray coating, and the like. The single layer of nanoparticle can be fused to the surface of the high refractive index adhesive layer by, for example, thermal sintering. The single layer of nanoparticle can be fused to the surface of the high refractive index adhesive layer by, for example, coating the surface of the particle or at the interface between the adhesive layer and the nanoparticle, for example, by adding an extremely thin layer. Very thin (such as having a thickness of 1 nm to 20 nm) such as decane, polymer, copolymer, adhesive, decane, sol-gel SiO ₂ material or the like applied by, for example, dip coating or spraying another material The layer can serve as an additional or second layer of adhesive.

In an embodiment, the nanoparticle monolayer may be first formed on an alkali metal tellurite glass substrate using, for example, dip coating, spin coating, spray coating, and the like, or a combination thereof. The single layer of nanoparticle can be fused to the surface of the alkali metal tellurite glass via thermal sintering. The alkali metal silicate glass can then be chemically strengthened as needed by, for example, ion exchange of smaller ions in the glass with larger natural ions, such as ion exchange of natural sodium ions with potassium ions. . Finally, the refractive index of the glass substrate below the single layer of nanoparticle can be improved by ion exchange in a bath containing metal ions such as silver particles having a high relative permittivity. This plasma exchange reaction has been shown to increase the refractive index of alkali metal citrate from, for example, 1.51 to 1.61 (see, for example, R. Araujo, "Colorless glasses containing ion-exchanged silver" Applied Optics , v. 31, 25, 5221-5224 pages). In order to produce a thin layer of high refractive index material using an ion exchange process, it is desirable to carry out ion exchange at low temperatures for a short period of time, such as a temperature of less than 450 ° C, or even less than 350 ° C, such as 250 ° C to 400 ° C, and a duration of less than 1 hour, less than 20 minutes, or even less than 5 minutes, such as a time interval of 1 minute to 60 minutes, including intermediate values and ranges. In some cases, it may be preferred to use electrostatically driven ion exchange at low temperatures to form a sharp diffusion profile.

In an embodiment, the glass substrate or the glass article may comprise one or more of or consist of one of the following: sodium calcium silicate glass, alkaline earth metal aluminosilicate glass, alkali metal aluminum bismuth Acid glass, alkali metal borosilicate glass, and combinations thereof. In an embodiment, the glass article may be, for example, an alkali metal aluminosilicate glass having the following composition: 60-72 mol% SiO ₂ , 9-16 mol% Al ₂ O ₃ , 5-12 mol% B ₂ O ₃ , 8-16 mol% Na ₂ O and 0-4 mol% K ₂ O, of which ratio The alkali metal modifier is an alkali metal oxide. In an embodiment, the alkali metal aluminosilicate glass substrate may be, for example, 61-75 mol% SiO ₂ , 7-15 mol% Al ₂ O ₃ , 0-12 mol% B ₂ O ₃ , 9-21 mol% Na ₂ O, 0-4 mol% K ₂ O, 0-7 mol% MgO, and 0-3 mol% CaO. In an embodiment, the alkali metal aluminosilicate glass substrate may be, for example, 60-70 mol% SiO ₂ , 6-14 mol% Al ₂ O ₃ , 0-15 mol% B ₂ O ₃ , 0-15 mol% Li ₂ O, 0-20 mol% Na ₂ O, 0-10 mol% K ₂ O, 0-8 mol% MgO, 0-10 mol% CaO, 0-5 mol% ZrO ₂ , 0-1 mol% SnO ₂ , 0-1 mol% CeO ₂ , less than 50 ppm As ₂ O ₃ and less than 50 ppm Sb ₂ O ₃ ; 12 mol% Li ₂ O+Na ₂ O+K ₂ O 20 mol% and 0 mol% MgO+CaO 10 mol%. In an embodiment, the alkali metal aluminosilicate glass substrate may be, for example, 64-68 mol% SiO ₂ , 12-16 mol% Na ₂ O, 8-12 mol% Al ₂ O ₃ , 0-3 mol% B ₂ O ₃ , 2-5 mol% K ₂ O, 4-6 mol% MgO, and 0-5 mol% CaO, of which: 66 mol% SiO ₂ +B ₂ O ₃ +CaO 69 mol%; Na ₂ O+K ₂ O+B ₂ O ₃ +MgO+CaO+SrO>10 mol%; 5 mol% MgO+CaO+SrO _{8mol%; (Na 2 O +} B 2 O 3) -Al 2 O 3 2 mol%; 2 mol% Na ₂ O-Al ₂ O ₃ 6 mol%; and 4 mol% (Na ₂ O+K ₂ O)-Al ₂ O ₃ 10 mol%. In an embodiment, the alkali metal aluminosilicate glass substrate may be, for example, 50-80 wt% SiO ₂ , 2-20 wt% Al ₂ O ₃ , 0-15 wt% B ₂ O ₃ , 1-20 wt% Na ₂ O, 0-10wt% Li ₂ O, 0-10wt% K ₂ O, and 0-5wt% (MgO+CaO+SrO+BaO), 0-3wt% (SrO+BaO), and 0-5wt% (ZrO ₂ +TiO ₂ ), where 0 (Li ₂ O+K ₂ O)/Na ₂ O 0.5. In an embodiment, the alkali metal aluminosilicate glass may, for example, be substantially free of lithium. In embodiments, the alkali aluminosilicate glass may, for example, be substantially free of at least one of: arsenic, antimony, bismuth, or combinations thereof. In an embodiment, the glass may optionally be treated in batches with 0 to 2 mol% of at least one fining agent such as Na ₂ SO ₄ , NaCl, NaF, NaBr, K ₂ SO ₄ , KCl, KF, KBr, SnO ₂ and Similar substances or combinations thereof.

In an embodiment, the selected glass can be, for example, pullable, or formed by a slot stretching or fusion stretching process such as is known in the art. In such cases, the glass can have a liquid phase viscosity of at least 130 kilopoise. An example of an alkali metal bismuth aluminide glass is described in the following: U.S. Patent Application Serial No. 11/888,213, filed on Jul. 31, 2007. </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> <RTIgt; "Glasses Having Improved Toughness and "Scratch Resistance", which claims the priority of U.S. Provisional Application No. 61/004,677, filed on November 29, 2007, which is incorporated herein by reference. Agents for Silicate Glasses, which claims priority to U.S. Provisional Application No. 61/067,130, filed on Feb. 26, 2008; U.S. Patent Application Serial No. 12/393,241, filed on Feb. 26, 2009. No., entitled "Ion-Exchanged, Fast Cooled Glasses", which claims priority to US Provisional Application No. 61/067,732, filed on February 29, 2008; Barefoot et al., filed on August 7, 2009 US Patent Application Serial No. 12/537,393, entitled "Strengthened Glass Articles and Methods of Making", which claims U.S. Provisional Application No. 61/087,324, entitled "Chemically Tempered Cover Glass", filed on August 8, 2008. Priority No. 61/235,767 to Barrefoot et al., filed on August 21, 2009, entitled "Crack and Scratch Resistant Glass and Enclosures Made Therefrom"; US Provisional Patent Application Dejneka et al., August 21, 2009 Application No. 61 / 235,762, titled "Zircon Compatible Glasses for Down Draw."

The glass surfaces and glass sheets described in the following examples can be coated with a glass substrate or the like using any suitable particles, and can include, for example, the glass compositions 1 to 11 listed in Table 5, or a combination thereof.

Instance

The following examples are provided to more fully describe the manner in which the above disclosure is used, and further illustrate the best mode contemplated for implementing various aspects of the present disclosure. It should be understood that these examples do not limit the scope of the disclosure, but are presented for illustrative purposes. Working examples further describe how to make the articles of the present disclosure.

Preparation of particle coated surface Example 1 (pre-example)

Preparation of a high refractive index binder layer. 200 mL of methanol was mixed with 25 mL of TEOS (tetraethyl ortho-decanoate or tetraethoxydecane, Aldrich) and 25 mL of 0.01 M HCl in water to give a solution having a pH of about 3. The mixture was stirred under reflux at about 65 ° C for 2 hours to form a solution "A". Separately, 126.5 mL of 2-ethoxyethanol was mixed with 2.86 mL of DI water, 0.64 mL of 69% HNO ₃ and 18.18 mL of Ti(IV) isopropoxide, while stirring, and the complete mixture was stirred under ambient conditions. The solution "B" was formed in 1 hour. Next, 1.6 mL of the solution "B" was mixed with 1.8 mL of the solution "A" and 2.0 mL of 2-propanol to form a coating solution "C". The coating solution "C" about 575rpm spin-coated onto a glass substrate (such as Corning Gorilla ^TM glass or Corning EagleXG ^TM) on for 60 seconds, followed by curing at 410 deg.] C in air for 1 hour and 15 minutes, thereby forming a relatively high refractive index of approximately 1.67 (n _g) and thickness (t) of the adhesive layer of the coating of about 75nm. This adhesive coating procedure can be repeated a second time to form a coating thickness of about 150 nm. Other adhesive layer coating thicknesses can be prepared with slight modifications to the concentration and coating conditions.

Example 2 (pre-example)

Preparation of nanoparticle coatings. A vermiculite nanosphere having a diameter of approximately 100 nm was dispersed in 2-propanol to form a suspension of about 1.5% solids. The pH of the suspension was adjusted to about 3.5 by the addition of HCl. If desired, the solution can be sonicated to promote good particle dispersion. The glass test piece sample can be dip coated in a nanoparticle suspension using an extraction speed of 30 mm/min to 35 mm/min to form a substantially single layer of 100 nm SiO ₂ nanoparticle on the glass surface. This procedure can be modified as needed by adjusting pH, solids content, temperature, humidity, and dip speed to form a similar coating on top of the first adhesive layer described above, and can be used at 400 The particles are sintered or partially sintered to a relatively high refractive index adhesive layer by heat treatment at ° C to 600 ° C for 1 hour or more.

Example 3 (pre-example)

The preparation of micronized surfaces having substantially uniform spacing or separation between adjacent particles, for example, uniform spacing of adjacent particles and non-close packed hexagonal geometry. Several recent methods have proven useful for fabricating non-closely packed nanoparticle monolayers with controlled spacing between particles on a variety of substrates, including proof of anti-reflective effects. These methods include: convective assembly on lithographic patterns (see Hoogenboom et al., "Template-Induced Growth of Close-Packed and Non-Close-Packed Colloidal Crystals during Solvent Evaporation", Nano Letters , 4, 2, Page 205, 2004.); dip coating of hydrogel spheres allows the hydrogel spheres to shrink during drying or heating after deposition (see Zhang et al., "Two-Dimensional Non-Close-Packing Arrays Derived From Self-Assembly of Biomineralized Hydrogel Spheres and Their Patterning Applications", Chem. Mater. 17, page 5268, 2005, and Figure 3 and associated text); spin coating and shear alignment of SiO ₂ nanospheres Add another material to this template as needed (see Venkatesh et al., "Generalized Fabrication of Two-Dimensional Non-Close-Packed Colloidal Crystals", Langmuir , 23, pp. 8231, 2007, and Figure 5 and associated Text); and electrostatically controlled self-assembly at the air-water or alkane-water interface while transferring to the substrate, using an extremely thin (about 17 nm) adhesive layer as needed (see Ray et al. "Submicrometer Surface Patterning Using Interfacial Colloidal Particle Self-Assembly", Langmuir, 25, p. 7265, 2009, and Fig. 8 and associated text; Bhawalkar et al., "Development of a Colloidal Lithography Method for Patterning Nonplanar Surfaces", Langmuir, 26, p. 16662, 2010). However, such prior work does not specify the desired relationship between particle size, particle spacing, particles sinking into the substrate or binder layer, and high refractive index binder layers. These relationships are indicated in the present disclosure and achieve excellent low reflection performance of visible light, along with enhanced durability due to optional particle sinking or sintering.

100‧‧‧AR objects

110‧‧‧Substrate

120‧‧‧Binder layer

130‧‧‧Nano particle single layer

Claims (9)

An antireflection article comprising: a transparent substrate having a refractive index (n _s ) of 1.48 to 1.53; an adhesive layer bonded to the substrate, the adhesive having a refractive index of 1.55 to 1.75 (n _g And a single or near monolayer of a nanoparticle combined with the binder layer, the nanoparticle monolayer or near monolayer having an effective refractive index (n _{p eff} less than the refractive index of the binder layer) ). The antireflection article of claim 1, wherein the effective refractive index (n _{p eff} ) of the nanoparticle monolayer is from 1.15 to 1.3. The antireflection article of claim 1, wherein the reflectivity of the article has an average reflectance of less than 0.2% over a spectral width of at least 100 nm covering at least a portion of the visible wavelength spectrum of 400 nm to 700 nm. The anti-reflection article of claim 1, wherein the nanoparticle monolayer comprises nanoparticles in a non-close packed hexagonal geometry having a pitch of 1.15 to 1.25 (p) and nano Particle diameter (D) ratio (p/D). The antireflection article of claim 1, wherein the binder has a thickness (g) of from 1 x D to 2 x D, wherein D is the average diameter (D) of the nanoparticle. The antireflection article of claim 1, wherein the transparent substrate is a glass, a polymer, a glass-ceramic, a crystalline oxide, a semiconductor or a combination of the foregoing. A method for producing the anti-reflection article according to claim 1, the method comprising the steps of: depositing a binder on the substrate; depositing nanoparticles to form a single layer of the nanoparticle on or near the binder a single layer; and the nanoparticles of the nanoparticle monolayer or the near monolayer are immobilized on the binder layer. The method of claim 7, wherein the step of fixing the nanoparticle monolayer to the adhesive layer comprises: thermally sintering; depositing a second adhesive on the adhesive and the deposited nanoparticle single Between the layers; depositing a second binder on the combined binder and the deposited nanoparticle monolayer; depositing a second binder on the deposited nanoparticle monolayer adjacent to the nanoparticle Between, or a combination of the foregoing steps. The method of claim 7, the method further comprising the step of: chemically strengthening the article by ion exchange of at least one of: the substrate before depositing the binder; the binder on the substrate; The substrate is fixed to the binder before the substrate is fixed to the binder; the substrate after deposition or after fixing the nanoparticle monolayer, or a combination of the foregoing.