JP2016186069A - Durable hybrid omnidirectional structural color pigments for exterior paint applications - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weather resistant hybrid omnidirectional structural color pigment.SOLUTION: A hybrid omnidirectional structural color pigment is in the form of a multilayer stack that has a reflective core layer and at least two high refractive index (n) layers. One of the nlayers can be a dry deposited dielectric layer that extends across the reflective core layer, and one of the layers can be a wet deposited nouter protective coating layer. An absorber layer that extends between the dry deposited ndielectric layer and the wet deposited outer protective layer can also be included.SELECTED DRAWING: Figure 16

Description

  The present invention has a multilayer laminate structure with a protective coating, and in particular, has a protective coating and exhibits minimal or unrecognizable color shift when exposed to broadband electromagnetic radiation and viewed from different angles. The present invention relates to a hybrid multilayer laminated structure.

<Cross-reference of related inventions>
This application is a continuation-in-part of U.S. Patent Application No. 14 / 471,834 filed on August 28, 2014, which is a part of U.S. Patent Application No. 14 / 460,511 filed on Aug. 15, 2014. A continuation-in-part application, which is a continuation-in-part of U.S. Patent Application No. 14 / 242,429 filed on April 1, 2014, which is filed on Dec. 23, 2013 No. 138,499, which is a continuation-in-part of U.S. Patent Application No. 13 / 913,402 filed on June 8, 2013, which is filed on Feb. 6, 2013. US Patent Application No. 13 / 760,699, which is a continuation-in-part of 13 / 572,071 filed on August 10, 2012, which is filed in February 2011. US patent application 13/0 filed 5 days No. 1,730, which is a continuation-in-part of US patent application 12 / 793,772 filed June 4, 2010 (US Pat. No. 8,736,959) This is a continuation-in-part of US patent application 12 / 388,395 (US Pat. No. 8,749,881) filed on Feb. 18, 2009, which was filed on August 12, 2007. Is a continuation-in-part of U.S. Patent Application No. 11 / 837,529 (U.S. Patent Application No. 7,903,339). US Patent Application No. 13 / 913,402 filed June 8, 2013 is a continuation-in-part of 13 / 014,398 filed January 26, 2011, which is dated June 4, 2010. This is a continuation-in-part of application 12 / 793,772, which is a continuation-in-part of 12 / 686,861 filed on January 13, 2010 (US Pat. No. 8,593,728). Yes, this is a continuation-in-part of 12 / 389,256 (US Pat. No. 8,329,247) filed on Feb. 19, 2009, all of which are incorporated by reference in their entirety. Is done.

  Pigments made from multilayer structures are known. In addition, pigments that exhibit or provide high color omnidirectional structural colors are further known. However, prior art pigments required as many as 39 thin film layers to obtain the desired color characteristics.

  It should be understood that the cost associated with the production of thin film multilayer pigments is proportional to the number of layers required. Thus, the costs associated with producing high color omnidirectional structural colors using multilayer stacks of dielectric materials can be very expensive. Therefore, high color omnidirectional structural colors that require minimal thin film layers are desirable.

  In addition to the above, it should be understood that pigments may fade, discolor, etc. when exposed to sunlight, and particularly ultraviolet light. Accordingly, there is a further need for weatherable, high chroma omnidirectional structural color pigments.

  Provides a hybrid omnidirectional structural color. This pigment exhibits a color visible to the human eye when exposed to broadband electromagnetic radiation (eg white light) and viewed from an angle between 0 ° and 45 ° and has a very small or unrecognizable color shift .

This pigment has the form of a multilayer stack that reflects a reflection band having a given half width (FWHM) of less than 300 nm, also referred to herein as a multilayer film. In addition, this reflection band has a given color shift less than 30 ° in the a ^* b ^* color map using CIELAB when exposed to broadband electromagnetic radiation and viewed from angles of 0 ° and 45 °. .

The multilayer stack has a reflective core layer and at least two high refractive index (n _h ) layers. One n _h layer may be a dry deposition n _h dielectric layer extending over the reflective core layer, also one of the layer, dry deposition extending over airlaid n _h dielectric layer It may be an absorber layer. The multilayer stack may further include an external protective layer that may be in the form of a wet deposited _nh external oxide layer. In some examples, the wet-deposited _nh outer oxide layer covers and is in direct contact with the dry-deposited absorber layer, and completely surrounds the reflector core layer and the at least two _nh layers or It may or may not be wrapped.

  This reflective core layer may be a metal reflector core layer having a thickness between 30 nm and 200 nm. In one example, the metal core reflector layer is made of at least one of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof.

The airlaid _{n h} dielectric _{layer, CeO 2, Nb 2 O 5} , SiN, SnO 2, SnS, TiO 2, at least one of ZnO, ZnS, and ZrO _2, or _{CeO 2,} Nb 2 _{O 5,} It is made from a mixture having at least one of SiN, SnO ₂ , SnS, TiO ₂ , ZnO, ZnS, and ZrO ₂ . In addition, the dry deposition n _h dielectric layer has a thickness of between 0.1QW~4.0QW for desired adjustment wavelength, the desired adjustment wavelength, the center wavelength of a desired color reflection bands It is. The dry deposition absorber layer is made of at least one of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, Fe ₂ O ₃ , and the like, and has a thickness between 2 nm and 30 nm. You may have. Wet deposition _{n h} outer oxide _{layer, CeO 2, Nb 2 O 5} , SnO 2, TiO 2, ZnO, and is made from at least one of ZrO _2, have a thickness between 5nm~200nm You can do it.

In some examples, the multilayer body has a central reflector core layer and a pair of dry deposited _nh dielectric layers disposed opposite each other and bonded to the reflective core layer. In addition, the pair of absorber layers may be disposed opposite each other and coupled to the pair of dry deposited _nh dielectric layers. Further, the wet deposition n _h outer oxide layer may extend across the outer surfaces of the pair of absorber layers.

  This hybrid omnidirectional structural color has a thickness of less than 2.0 μm and, in some examples, a thickness of less than 1.5 μm. The pigment, and thus the multilayer laminate, may have a total of fewer than 10 layers, and in some instances may have a total of fewer than 8 layers.

Further provided is a method of making an omnidirectional structural color pigment. The method comprises providing a reflective core layer, and by dry deposition of n _h dielectric layer extending over the reflective core layer includes fabricating a multilayer laminate described above. Additionally, the method includes the dry deposit the absorber layer extending over n _h dielectric layer, and that the wet deposition of external n _h oxide layer extending over the absorber layer.

FIG. 1 is a schematic diagram of an omnidirectional structural color multilayer stack made of a dielectric layer, a selectively absorbing layer (SAL) and a reflector layer. FIG. 2A is a schematic diagram of zero or near zero electric field points in a ZnS dielectric layer exposed to electromagnetic radiation (EMR) having a wavelength of 500 nm. FIG. 2B shows the thickness of the ZnS dielectric layer shown in FIG. 2A exposed to EMR having wavelengths of 300 nm, 400 nm, 500 nm, 600 nm, and 700 nm, versus the square of the absolute value of the electric field (| E | ² ). FIG. FIG. 3 is a schematic illustration of a dielectric layer extending over a substrate or reflector layer and exposed to electromagnetic radiation from an angle θ relative to the normal direction of the outer surface of the dielectric layer. FIG. 4 is a schematic diagram of a ZnS dielectric layer in which a Cr absorber layer is disposed at a zero or near zero electric field point for incident EMR having a wavelength of 434 nm in the ZnS dielectric layer. FIG. 5 shows the reflection versus percent reflectance when a multilayer stack without a Cr absorber layer (eg, FIG. 2A) and a multilayer stack with a Cr absorber layer (eg, FIG. 4) are exposed to white light. It is a graph display of an EMR wavelength. FIG. 6A is a graphical representation of first and second harmonics represented by a ZnS dielectric layer (eg, FIG. 2A) extending over an Al reflector layer. 6B shows a ZnS dielectric layer extending over the Al reflector layer and a Cr absorber layer disposed in the ZnS dielectric layer so that the second harmonic as shown in FIG. 6A is absorbed. 2 is a graph of reflected EMR wavelength versus reflectance percent for a multilayer stack having. 6C shows a ZnS dielectric layer extending over the Al reflector layer and a Cr absorber layer disposed in the ZnS dielectric layer so that the first harmonic as shown in FIG. 6A is absorbed. 2 is a graph of reflected EMR wavelength versus reflectance percent for a multilayer stack having. FIG. 7A is a graph of the thickness of the dielectric layer versus the square of the electric field, showing the electric field angle dependence of the Cr absorber layer when exposed to incident light from 0 ° and 45 °. FIG. 7B shows the reflection against the percent absorption by the Cr absorber layer when exposed to white light from angles of 0 ° and 45 ° relative to the normal direction of the outer surface (0 ° is perpendicular to the surface). It is a graph of an EMR wavelength. FIG. 8A is a schematic representation of a red omnidirectional structural color multilayer stack, according to certain embodiments disclosed herein. 8B is a graph of reflected EMR wavelength versus absorptance percentage of the Cu absorber layer shown in FIG. 8A when white light is exposed to the multilayer stack shown in FIG. 10A at incidence angles of 0 ° and 45 °. It is. FIG. 9 is a graphical comparison of calculated / simulated data and experimental data for reflected EMR wavelength to prove the concept of a red omnidirectional structural color multilayer stack exposed to white light at an incident angle of 0 °. FIG. 10 is a graph of wavelength versus reflectance percentage for an omnidirectional structural color multilayer stack according to certain embodiments disclosed herein. FIG. 11 is a graph of wavelength versus reflectance percentage for an omnidirectional structural color multilayer stack according to certain embodiments disclosed herein. FIG. 12 is a graph of percent reflectance versus wavelength for an omnidirectional structural color multilayer stack according to certain embodiments disclosed herein. FIG. 13 is a graph of reflectance versus wavelength for omnidirectional structural color multilayer stacks according to certain embodiments disclosed herein. FIG. 14 compares a saturation and color shift between a conventional paint and a paint made from a pigment according to certain embodiments disclosed herein (sample (b)), a ^* b using CIELAB. ^{* This} is a graphical representation of part of the color map. FIG. 15 is a schematic illustration of an omnidirectional structural color multilayer stack according to certain embodiments disclosed herein. FIG. 16 is a schematic illustration of a five-layer omnidirectional structured color pigment with a protective coating, according to certain embodiments disclosed herein. FIG. 17 is a schematic illustration of a protective coating having two or more layers according to certain embodiments disclosed herein. FIG. 18 is a schematic illustration of an omnidirectional structural color multilayer stack according to certain embodiments disclosed herein. FIG. 19 is a schematic illustration of a seven-layer omnidirectional structural color pigment with a protective coating, according to certain embodiments disclosed herein.

An omnidirectional structural color pigment is provided. This omnidirectional structural color reflects a narrow band of electromagnetic radiation in the visible spectrum and is small or unrecognizable when the multilayer stack is viewed by the human eye from an angle between 0 ° and 45 °. It has the form of a multi-layer laminate (herein further referred to as “multi-layer thin film”) having a deviation. More professionally, this multilayer stack reflects a narrow band of visible electromagnetic radiation less than 300 nm when exposed to white light. In addition, when this pigment is observed from an angle between 0 ° and 45 ° with respect to the vertical direction of the outer surface of the multilayer laminate, the narrow band of reflected visible light is a ^* b using CIELAB. ^{* In the} color map, shift smaller than 30 °.

The multilayer stack includes a reflector core layer, a high refractive index (n _h ) dielectric layer extending across the reflector core layer, an absorber layer extending across the n _h dielectric layer, and an absorber layer extending _Nh external protective layer. In one example, the narrow band of reflected electromagnetic radiation has a FWHM defined below, which is less than 200 nm and in another example less than 150 nm. The multilayer stack may further have a color shift of less than 20 ° in the a ^* b ^* color map and in some instances less than 15 °.

  Another criterion for color shift is the shift of the center wavelength of the narrow reflection band. In this respect, when the multilayer laminate is exposed to broadband electromagnetic radiation and observed from an angle between 0 ° and 45 ° with respect to the vertical direction of the outer surface of the multilayer laminate, the narrow band of reflected visible light is reduced. The center wavelength is shifted below 50 nm, preferably below 40 nm, more preferably below 30 nm. Furthermore, the multilayer stack may or may not have a separate reflection band of electromagnetic radiation in the UV and / or IR region.

  The total thickness of the multilayer stack is less than 2 μm, preferably less than 1.5 μm, and even more preferably less than 1.0 μm. Therefore, this multilayer laminate can be used as a paint pigment for thin paint coatings.

  The multilayer stack includes a reflector core layer from which a first layer and a second layer extend, and the reflector core layer is made of a metal such as Al, Ag, Pt, Cr, Cu, Zn, Au. , Sn, their alloys, and the like. The reflector core layer usually has a thickness between 30 nm and 200 nm.

The first layer is made from an _nh dielectric material and the second layer is made from an absorptive material. n _h dielectric _{material, CeO 2, Nb 2 O 5} , SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and may but include ZrO _2, but is not limited thereto. The absorptive material may be a selectively absorptive material such as Cu, Au, Zn, Sn, alloys thereof, and the like, or alternatively, a colored dielectric material such as Fe ₂ O ₃ , Cu ₂ O, these And the like, and the like. The absorbent material is further a non-selective absorbent material such as Cr, Ta, W, Mo, Ti, Ti nitride, Nb, Co, Si, Ge, Ni, Pd, V, iron oxide, combinations or alloys thereof, And the like. Outer protective _{layer, CeO 2, Nb 2 O 5} , SnO 2, TiO 2, ZnO, and may but contain ZrO _2, not limited thereto.

The thickness of the n _h dielectric layer may be between 0.1QW~4.0QW for desired adjustment wavelength. The thickness of the absorbent layer made from the selectively absorbent material is between 20 nm and 80 nm, while the thickness of the absorbent layer made from the non-selective absorbent material is between 5 nm and 30 nm. . The thickness of the external protective layer may be between 5 nm and 200 nm.

  The multilayer stack may have a reflected narrow band of electromagnetic radiation having a symmetrical peak shape in the visible spectrum. Alternatively, the reflected narrowband of electromagnetic radiation in the visible spectrum may be adjacent to the UV region, so that a portion of the reflected narrowband of electromagnetic radiation, eg, the UV portion, is not visible to the human eye. In another alternative, the reflection band of electromagnetic radiation may have a portion in the IR region, so that the IR portion is not visible to the human eye.

Whether the reflection band of electromagnetic radiation in the visible region is in contact with the UV region, the IR region, or has a symmetrical peak in the visible spectrum, the multilayer stack disclosed herein is visible. It has a narrow band of reflected electromagnetic radiation in the spectrum, which is low, small or has an unrecognizable color shift. Low or unrecognizable color shifts may be in the form of small shifts in the central wavelength of the reflected narrow band of electromagnetic radiation. Alternatively, the low or unrecognizable color shift may be in the form of a UV side edge of the reflection band of electromagnetic radiation that is in contact with the IR or UV region, respectively, or a small shift of the IR side edge. A small shift of such center wavelength, UV side edge, and / or IR side edge when observing the multilayer stack from an angle between 0 ° and 45 ° relative to the vertical direction of the outer surface of the multilayer stack. Is typically less than 50 nm, in some instances less than 40 nm, and in other examples less than 30 nm. This low or unrecognizable color shift may also be in the form of a small color shift on the a ^* b ^* color map using the CIELAB color space. For example, in certain instances, the color shift for a multilayer laminate is less than 30 °, preferably less than 25 °, more preferably less than 20 °, even more preferably less than 15 °, and even more preferably 10 Less than °.

In addition to the above, the omnidirectional structural color that is in the form of a multilayer laminate may be in the form of a plurality of pigment particles having an external protective coating, such as a weather resistant coating. The outer protective coating may include one or more _nh oxide layers that reduce the relative photocatalytic reaction of the pigment particles. In one example, the outer protective coating includes a first oxide layer and a second oxide layer. In addition, the first oxide layer and / or the second oxide layer may be a hybrid oxide layer, ie, an oxide layer that is a combination of two oxides.

  The method of making the omnidirectional structural color pigment may or may not involve the use of acids, acidic compounds, acidic solutions, and the like. In other words, the plurality of omnidirectional structural color pigment particles may or may not be treated with an acidic solution. Further teachings and details about omnidirectional structural color pigments and methods of making the pigments are discussed later herein.

Referring to FIG. 1, a design having a _first dielectric material layer DL ₁ over which an underlying reflector layer (RL) extends, and a selectively absorbing layer SAL extending over the DL ₁ layer, It is shown. In addition, another DL ₁ layer may be provided and may or may not extend across the selective absorbent layer. In addition, a diagram is shown in which all incident electromagnetic radiation is reflected or selectively absorbed by the multilayer stack.

  The design as represented in FIG. 1 corresponds to different approaches for designing and manufacturing the desired multilayer stack. In particular, the zero or near zero energy point thickness of the dielectric layer is used and discussed below.

  For example, FIG. 2A is a schematic illustration of a ZnS dielectric layer extending over an Al reflector core layer. This ZnS dielectric layer has a total thickness of 143 nm and has an energy point of zero or nearly zero at 77 nm for incident electromagnetic radiation having a wavelength of 500 nm. In other words, for incident electromagnetic radiation (EMR) having a wavelength of 500 nm, the ZnS dielectric layer represents a zero or nearly zero electric field point at a distance of 77 nm from the Al reflector layer. In addition, FIG. 2B provides a graph of the energy field across the ZnS dielectric layer for a number of different incident EMR wavelengths. As shown in the graph, the dielectric layer has an electric field of zero or nearly zero at a thickness of 77 nm for a wavelength of 500 nm, but at a thickness of 77 nm for EMR wavelengths of 300 nm, 400 nm, 600 nm, and 700 nm. Has a non-zero electric field.

Calculation of zero or near-zero field point, Figure 3, on a substrate or core layer 2 having a refractive index n _s, the total thickness "D", the incremental thickness "d", and a refractive index "n" The dielectric layer 4 having Incident light strikes the outer surface 5 of the dielectric layer 4 at an angle θ with respect to a line 6 perpendicular to the outer surface 5 and is reflected from the outer surface 5 at the same angle θ. Incident light passes through the outer surface 5, enters the dielectric layer 4 at an angle θ _F with respect to the line 6, and strikes the surface 3 of the substrate layer 2 at an angle θ _s .

When z = d, for one dielectric layer, θ _s = θ _F and the energy / electric field (E) can be expressed as E (z). From Maxwell's equations, for s-polarized light:
Also for p-polarized light:
Where k = 2π / λ, where λ is the desired wavelength to be reflected. Furthermore, α = _n sin θ _s , where “s” corresponds to the substrate in FIG.
Is the dielectric constant of this layer as a function of z.
Therefore, for s-polarized light,
And p-polarized light
It is.

It should be understood that the change in the electric field in the Z-axis direction of the dielectric layer 4 can be approximated by calculating the unknown parameters u (z) and v (z), which can be shown as follows:
Of course, “i” is the square root of −1. boundary condition
And using the following relationship:
For s-polarized light, q _s = n _s cos θ _s (6)
For p-polarized light, q _s = n _s / cos θ _s (7)
For s-polarized light, q _F = n cos θ _F (8)
For p-polarized light, q _F = n / cos θ _F (9)
φ = k · n · dcos (θ _F ) (10)
u (z) and v (z) can be expressed as follows:
as well as
Therefore, for s-polarized light,
Using:
And for p-polarized light:
here,
as well as

Thus, in a simple condition where θ _F = 0 or normal incidence, φ = k · n · d and α = 0:
| E (d) | ^{2 for} p-polarized light
This can be solved for a thickness “d”, eg, a location or location where the electric field in the dielectric layer is zero.

  Referring to FIG. 4, Equation 19 was used to calculate a zero or near zero field point in the ZnS dielectric layer shown in FIG. 2A when exposed to an EMR having a wavelength of 434 nm. The zero or near zero field point was calculated to be 70 nm (versus 77 nm for a 500 nm wavelength). In addition, a 15 nm thick Cr absorber layer was inserted at a thickness or distance of 70 nm from the Al reflector core layer to obtain a zero or near zero electric field ZnS-Cr boundary. Such an original structure allows light having a wavelength of 434 nm to pass through the Cr-ZnS boundary, but absorbs light having no wavelength of 434 nm. In other words, this Cr-ZnS boundary has a zero or nearly zero electric field for light having a wavelength of 434 nm, so that 434 nm light is transmitted through this boundary. However, the Cr—ZnS boundary does not have a zero or nearly zero electric field point for light that does not have a wavelength of 434 nm, so that such light is absorbed by the Cr absorber layer and / or the Cr—ZnS boundary. , Not reflected by the Al reflector layer.

  It should be understood that a few percent of the desired 434 nm +/− 10 nm light passes through the Cr—ZnS boundary. However, it should be understood that such a narrow band of reflected light, eg 434 +/− 10 nm, still provides a clear structural color to the human eye.

  The results for the Cr absorber layer in the multilayer stack of FIG. 4 are shown in FIG. 5, where the reflectivity percentage relative to the reflected EMR wavelength is shown. As shown by the dotted line corresponding to the ZnS dielectric layer shown in FIG. 4 without the Cr absorber layer, there is a narrow reflection peak at about 400 nm, but there is a wider peak at about 550+ nm. In addition, there is still a large amount of reflected light in the 500 nm wavelength region. Thus, there are two peaks that prevent the multilayer stack from exhibiting a structural color.

  In contrast, the solid line shown in FIG. 5 corresponds to the structure of FIG. 4 having a Cr absorber layer. As shown in the figure, there is a sharp peak at about 434 nm, and a sharp decrease in reflectivity for wavelengths greater than 434 nm is obtained with the Cr absorber layer. It should be understood that sharp peaks represented by solid lines appear as visually sharp / structural colors. Furthermore, FIG. 5 measures the reflection peak or band width, for example, where the band width is measured at half the maximum of the reflection wavelength, also known as the half width (FWHM).

  By designing or setting the thickness of the ZnS dielectric layer for the omnidirectionality of the multilayer structure shown in FIG. 4, only the first harmonic of the reflected light can be provided. It should be understood that this is sufficient to obtain a “blue” color, however, the creation of a “red” color requires further consideration. For example, adjusting the angle independence for red is difficult because it requires a thicker dielectric layer, which results in a high harmonic design, ie the second and third harmonics to be present. Waves are inevitable. Furthermore, the dark brown color space is very narrow. Thus, the red multilayer stack has a high angular change.

In order to overcome this high angular change in red, this application discloses a design / structure that provides a unique and novel, angle-independent red. For example, FIG. 6A shows a dielectric that exhibits first and second harmonics for incident white light when the outer surface of this dielectric layer is observed from an angle of 0 ° to 45 ° with respect to the vertical direction of the outer surface. Represents a layer. As shown in this graphical representation, a low angular dependence (small Δλ _c ) is provided by the thickness of the dielectric layer, but such multilayer stacks are blue (first harmonic) and red (Second harmonic) combination, and therefore not suitable for the desired “red only” color. Hence, this theory / structure has been developed that utilizes absorber layers to absorb undesired groups of harmonics. FIG. 6A shows the position of the central wavelength (λ _c ) of the reflection band of a given reflection peak and the dispersion or shift (Δλ _c) of this central wavelength when the sample is observed from an angle between 0 ° and 45 °. ).

Referring to FIG. 6B, the second harmonic shown in FIG. 6A is absorbed by the Cr absorber layer at a suitable dielectric layer thickness (eg, 72 nm) and results in a sharp blue color. Further, FIG. 6C shows that the first harmonic is absorbed by the Cr absorber layer at different dielectric layer thicknesses (eg, 125 nm), resulting in a red color. However, FIG. 6C further illustrates that the use of a Cr absorber layer can result in a higher angular dependence than that desired for this multilayer stack, ie greater than the desired Δλ _c .

The relatively large shift of λ _c for red compared to blue means that this dark red color space is very narrow and that the Cr absorber layer absorbs colors corresponding to non-zero or nearly non-zero electric fields. That is, due to the fact that when this electric field is zero or nearly zero, it does not absorb light. Thus, FIG. 7A shows that this zero or near-zero electric field point for the light wavelength is different for different incident angles. Such factors lead to the angle-independent absorptivity shown in FIG. 7B, ie the difference between the absorption curves at 0 ° and 45 °. Therefore, in order to further improve the design of the multilayer stack and the angle-independent performance, for example, an absorber layer that absorbs blue light is used regardless of whether the electric field is zero or not.

  In particular, FIG. 8A shows a multilayer stack in which a Cu absorber layer extends over a ZnS layer instead of a Cr absorber layer. The result of using such a “colored” or “selective” absorber layer is shown in FIG. 8B, which is more “of the 0 ° and 45 ° absorptance lines of the multilayer stack shown in FIG. 8A. It represents a “serious” grouping. Thus, the comparison between FIG. 8B and FIG. 7B shows that there is a significant improvement in the angle independence of the absorption rate by using a selective absorber layer instead of a non-selective absorber layer. ing.

  Based on the above, a multilayer laminate structure for proof of concept was designed and fabricated. In addition, the calculation / simulation results for the samples to prove the concept and the actual experimental data were compared. In particular, and as shown in the graph plot of FIG. 9, a bright red color is produced (wavelengths greater than 700 nm are usually not visible to the human eye), and calculations / simulations and experiments obtained from actual samples A very good agreement was obtained with the light data. In other words, the calculation / simulation can be used to simulate or simulate the results of one or more embodiments of the present invention and / or the multilayer stack design of known multilayer stacks.

  An inventory of simulated and / or actually produced multilayer stack samples is provided in Table 1 below. As shown in the table, the inventive design disclosed herein includes at least five different layer structures. In addition, this sample was simulated and / or made from a wide area of material. The result was a sample exhibiting high saturation, low color shift (Δh), and excellent reflectance. In addition, the 3 and 5 layer samples have a total thickness between 120 and 200 nm; the 7 layer sample has a total thickness of 350 to 600 nm; the 9 layer sample has a total thickness of 440 to 500 nm. The 11 layer sample had a total thickness of 600-660 nm.

  Referring to FIG. 10, a plot of reflected EMR wavelength versus percent reflectance is shown for an omnidirectional reflector when exposed to white light from angles of 0 ° and 45 ° relative to the vertical direction of the outer surface of the reflector. ing. As shown in the plot, the 0 ° and 45 ° curves represent the very low reflectivity provided by the omni-directional reflector for wavelengths greater than 500 nm, eg less than 20%. However, this reflector provides a sharp increase in reflectivity at wavelengths between 400 and 500 nm, as shown by the curve, and reaches a maximum of about 90% at 450 nm. It should be understood that the portion or area of the graph on the left hand side (UV side) of this curve represents the UV portion of the reflection band provided by this reflector.

This sharp increase in reflectivity provided by this omnidirectional reflector is characterized by the IR side edge of each curve extending from a low reflectivity portion at a wavelength greater than 500 nm to a high reflectivity portion, eg,> 70%. It is done. The straight line portion 200 on the IR end side is inclined at an angle (β) larger than 60 ° with respect to the x-axis, and has a length L of about 50 on the reflectance axis and an inclination of 1.2. In one example, the straight portion is inclined at an angle greater than 70 ° with respect to the x-axis, while in other examples β is greater than 75 °. Furthermore, the reflection band has a visible FWHM less than 200 nm, in some examples a visible FWHM less than 150 nm, and in other examples a visible FWHM less than 100 nm. In addition, the center wavelength λ _c of the visible reflection band as shown in FIG. 10 is defined as a wavelength that is equidistant from the IR side end of the reflection band and the UV end of the UV spectrum of the visible FWHM.

  The term “visible FWHM” is the width of the reflection band between the IR end of this curve and the end of the UV spectral region beyond which the reflection provided by the omnidirectional reflector is not visible to the human eye. Is mentioned. Thus, the inventive designs and multilayer laminates disclosed herein use the invisible UV portion of electromagnetic radiation to provide a sharp structural color. In other words, despite the fact that this reflector reflects a wider band of electromagnetic radiation that extends into the UV region, the omnidirectional reflector disclosed herein reduces the reflected narrow band of visible light. To provide, the invisible UV portion of the electromagnetic radiation spectrum is utilized.

Referring to FIG. 11, there is shown an overall left-right symmetric reflection band resulting from observing a multilayer stack according to an embodiment of the present invention from 0 ° and 45 °. As shown in the figure, the reflection band provided by the multilayer stack has a central wavelength λ _c (0 °) when viewed from 0 ° and a central wavelength λ _c (45 °) when viewed from 45 °. Furthermore, when the multilayer stack is viewed from an angle between 0 ° and 45 °, the shift of the center wavelength is less than 50 nm, ie Δλ _c (0−45 ^o ) <50 nm. In addition, the FWHM of this 0 ° reflection band and 45 ° reflection band is less than 200 nm.

  FIG. 12 is a plot of percent reflectivity versus reflected EMR wavelength for another omnidirectional reflector design when exposed to white light from angles of 0 ° and 45 ° relative to the normal to the surface of the reflector. Is shown. As shown in the plot, both the 0 ° and 45 ° curves represent very low reflectivity, eg, less than 10%, provided by the omnidirectional reflector for wavelengths less than 550 nm. However, as shown by the curve, this reflector provides a sharp increase in reflectivity at wavelengths between 560 nm and 570 nm, reaching about 90% of the maximum at 700 nm. It should be understood that the portion or region of the graph on the right hand side (IR side) of this curve represents the IR portion of the reflection band provided by this reflector.

This sharp increase in reflectivity provided by this omnidirectional reflector is characterized by the UV side edge of each curve extending from a low reflectivity portion at a wavelength less than 550 nm to a high reflectivity portion, eg,> 70%. It is done. The straight line portion 200 on the UV end side is inclined at an angle (β) larger than 60 ° with respect to the x-axis, and has a length L of about 40 on the reflectance axis and an inclination of 1.4. In one example, the straight portion is inclined at an angle greater than 70 ° with respect to the x-axis, while in other examples β is greater than 75 °. Furthermore, the reflection band has a visible FWHM less than 200 nm, in some examples a visible FWHM less than 150 nm, and in other examples a visible FWHM less than 100 nm. In addition, the center wavelength λ _c of this visible reflection band shown in FIG. 12 is defined as a wavelength that is equidistant from the UV side end of the reflection band and the IR end of the IR spectrum of the visible FWHM.

  The term “visible FWHM” is the width of the reflection band between the UV end of this curve and the end of the IR spectral region beyond which the reflection supplied by the omnidirectional reflector is not visible to the human eye. Should be understood as referring to. Thus, the inventive designs and multi-layer laminates disclosed herein use the invisible IR portion of electromagnetic radiation to provide a sharp structural color. In other words, despite the fact that the reflector reflects a wider band of electromagnetic radiation that extends into the IR region, the omnidirectional reflector disclosed herein provides a narrow band of reflected visible light. In order to do so, the invisible IR portion of the electromagnetic radiation spectrum is utilized.

Referring to FIG. 13, there is a plot of reflectance versus wavelength for another seven-layer design omnidirectional reflector when exposed to white light from angles of 0 ° and 45 ° to the surface of the reflector. Show. In addition, it provides a definition or evaluation of the omnidirectional characteristics provided by the omnidirectional reflector disclosed herein. In particular, and when the reflection band produced by the reflector of the present invention is maximum, i.e., has a peak as shown in the figure, each curve exhibits a maximum reflectance or a center wavelength (λ _c ) defined as the wavelength experienced. Have The term maximum reflection wavelength is also used as λ _c .

As shown in FIG. 13, the surface of the omni-directional reflector is taken from an angle (λ _c (45 ^o ) of 45 ^° ), for example, the angle at which the outer surface is inclined at 45 ° relative to the eyes of the viewer. when observed, an angle of _{0 ° (λ c (0 o} )), for example compared to when observing the surface from a vertical direction with respect to the surface, there is a shift or displacement of the lambda _c. this shift in lambda _c ( Δλ _c ) yields a measure of the omnidirectional characteristics of the omnidirectional reflector, which of course is a perfect omnidirectional reflector when there is zero shift, ie no shift at all. The directional reflector appears to the human eye as if the color of the reflector's surface did not change, so from a practical standpoint this reflector is omnidirectional and provides a Δλ _c of less than 50 nm. In some examples, the specification Shimesuru omnidirectional reflector may provide a [Delta] [lambda] _c of less than 40 nm, in other instances it is possible to provide a [Delta] [lambda] _c of less than 30 nm, in yet another embodiment, provides a [Delta] [lambda] _c of less than 20nm In yet other examples, a Δλ _c of less than 15 nm can be provided, such a shift of Δλ _c can be obtained by plotting the wavelength against the actual reflectivity of the reflector, and / or alternatively If the material and layer thicknesses are known, they can be measured by reflector modeling.

Another definition or characteristic of the omnidirectional characteristic of the reflector can be measured by an end shift of a given angular reflection band. For example, referring to FIG. 10, the omnidirectional reflector was observed from 0 °, compared to the IR side end (S _IR (45 ^o )) of the reflectance when the same reflector was observed from 45 °. The shift or displacement (ΔS _IR ) of the IR side edge (S _IR (0 ^o )) with respect to the reflectivity of time sometimes yields an omnidirectional characteristic measure of the omnidirectional reflector. In addition, when using Δλ _c , eg, a reflector that provides a reflectance band similar to that shown in FIG. 10 or FIG. 12, ie for a reflection band extending into the UV or IR region of EMR, ΔS It is preferred to use _IR as an omnidirectional quantity. It should be understood that the IR side edge shift (ΔS _IR ) can be measured and / or done in the visible FWHM.

With reference to FIG. 12, the reflection when the omnidirectional reflector is observed from 0 °, compared with the IR side end (S _UV (45 °)) of the reflectance when the same reflector is observed from 45 °. The shift or displacement (ΔS _IR ) of the IR side edge (S _UV (0 °)) for the rate provides a measure of the omnidirectional characteristics of the omnidirectional reflection pair. It should be understood that the UV edge shift (ΔS _UV ) can be measured and / or done in the visible FWHM.

Of course, a zero shift, ie no shift at all (ΔS _i = 0 nm; i = IR, UV), characterizes a perfect omnidirectional reflector. However, the omnidirectional reflector disclosed herein can provide a ΔS _L of less than 50 nm, which makes it appear to the human eye that the color of the reflector's surface does not change, and is therefore a practical standpoint. From the point of view, this reflector is omnidirectional. In some examples, the omni-directional reflector disclosed herein can provide a ΔS _i of less than 40 nm, in other examples ΔS _i is less than 30 nm, and in other examples ΔS _i is 20 nm. In still other examples, ΔS _i is less than 15 nm. Such a shift in ΔS _i can be measured by plotting the wavelength against the actual reflectivity of the reflector and / or alternatively by modeling the reflector if the material and layer thickness are known. .

The shift in omnidirectional reflection can be measured by a lower color shift. For example, as shown in FIG. 14 (see, for example, Δθ ₁ and Δθ ₃ ), the color shift of a pigment made from a multilayer laminate according to embodiments disclosed herein is less than 30 °, In certain instances, the color shift is less than 25 °, preferably less than 20 °, more preferably less than 15 °, and even more preferably less than 10 °. In contrast, conventional pigments exhibit a color shift of 45 ° or greater (see, for example, Δθ ₂ and Δθ ₄ ). It should be understood that the color shift for Δθ ₁ generally corresponds to red, however, the low color shift is relevant for any color reflected by the hybrid omnidirectional color pigment disclosed herein. . For example, the low color shift Δθ ₃ shown in FIG. 14 generally corresponds to the blue color produced by the hybrid omnidirectional structural color pigment of the embodiment, whereas the large color shift represented by the conventional blue pigment is Δθ represented by _4.

  An omnidirectional multilayer stack according to another embodiment disclosed herein is indicated by reference numeral 10 in FIG. The multilayer stack 10 includes a first layer 110 and a second layer 120. An optional reflector layer 100 may be included. Exemplary materials for the reflector layer 100, sometimes referred to as the reflector core layer, may include Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof. It is not limited to. Thus, the reflector 100 may be a metal reflector layer, however this is not essential. In addition, exemplary thicknesses of the core reflector layer range between 30 nm and 200 nm.

  The pair of symmetrical layers may be on the opposite side of the reflector layer 100, that is, the reflector layer 100 has another first layer disposed on the opposite side of the first layer 110. In this way, the reflector 100 is sandwiched between the pair of first layers. In addition, another second layer 120 may be disposed on the opposite side of the reflector layer 100, resulting in a five-layer structure. Therefore, it should be understood that the discussion of multi-layer stacks herein further includes the possibility of mirror structures for one or more core layers. Accordingly, FIG. 15 may be a half view of a five layer multilayer stack.

The first layer 110 is a high refractive index (n _h ) dielectric layer and may be a dry deposit. For the purposes of this disclosure, the term “high refractive index material” refers to a material having a refractive index equal to or greater than 2.0. Furthermore, the term “dry deposit” refers to a layer deposited and / or formed by dry deposition methods known to those skilled in the art, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD). . Further, the term “dry deposition method” refers to depositing the layer using dry deposition techniques known to those skilled in the art.

Exemplary materials for the dry deposition _{n h} dielectric layer _{110, CeO 2, Nb 2 O 5} , SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and including ZrO _2, but is not limited thereto. In addition, the dry deposition n _h dielectric layer may have a thickness of between 0.1QW and 4.0QW the desired adjustment wavelength, the desired adjustment wavelength, the center wavelength of the desired reflection band It is. The term “QW” or “QW thickness” refers to a quarter thickness of the desired tuning wavelength, ie QW = λ _cw / 4, where λ _cw is the desired tuning wavelength. .

The second layer 120 may be a dry deposition absorber layer. Exemplary absorber layer materials include, but are not limited to, Cr, Cu, Au, Sn, alloys thereof, amorphous Si, and Fe ₂ O ₃ , and the thickness of the second layer 120 is preferably Between 2 nm and 30 nm.

FIG. 16 is a five-layer design pigment 10a having a symmetrical layer with an outer protective layer 200 extending across the reflector core layer 100. FIG. The pigment 10a has a dry deposition _{n h} dielectric layer 110a and dry the absorber layer 120a is disposed to face. The outer protective layer 200 may be a wet deposition protective layer and / or an _nh oxide layer. The term “wet deposit” is deposited and / or formed using wet chemical techniques known to those skilled in the art, such as sol-gel processing, layer-by-layer processing, spin coating and the like. It should be understood as referring to layers. Typical examples of wet-laid layer _{material, CeO 2, Nb 2 O 5} , SnO 2, TiO 2, ZnO, and includes a ZrO _2, and the thickness of such a layer in the range of 5nm~200nm It may be.

An incomplete inventory of materials from which dry deposited _nh dielectric layers and / or wet deposited _nh outer protective layers can be made is shown in Table 2 below.

In one example, the outer protective layer 200 may be made from two wet deposited layers as depicted in FIG. As an example, the wet deposition layer 202 may be a first _nh oxide and the wet deposition layer 204 may be a second _nh oxide. In addition, the single outer protective layer 200, layer 202, and / or layer 204 may be a mixed _nh oxide layer that includes one or more _nh oxides.

It should be understood that the five-layer design shown in FIG. 16 has absorber layers 120 and 120a directly adjacent to or underneath the outer protective layer 200. In other words, the five-layer design pigment produced by dry deposition and before coating the outer protective layer has an outer absorber layer and a non-outer dielectric layer. It should be further understood that the outer protective layer can function not only as a protective layer but also as a color enhancement layer. By way of example and for illustrative purposes only, the outer protective layer 200 can only act as a protective coating and has no effect on the color represented by the pigment 10a. Therefore, the overall color of the pigment 10a is provided by the reflector core layer 100, airlaid _{n h} dielectric layer 110 and 110a, and the absorber layer 120, 120a. Alternatively, this outer protective layer 200 increases some color effects on the pigment 10a, such as increasing the saturation of the pigment and causing a slight shift in the “color” represented by the human eye of the pigment, It results in a slight increase in the omnidirectionality of the pigment (ie, a decrease in color shift), a slight decrease in the omnidirectionality of the pigment, and the like.

Referring to FIG. 18, another embodiment of the multilayer laminate of the present invention is shown at reference numeral 20. The multilayer stack 20 is similar to the multilayer stack 10 except for an additional absorber layer 105 that extends between the reflector core layer 100 and the dry deposited _nh dielectric layer 110. Further similar to the pigment 10a shown in FIG. 16, a pigment 20a is shown in FIG. 19 in which symmetrical layers 105a, 110a, and 120a extend across the reflector core layer 100 and are each layer 105. , 110 and 120 are arranged opposite to each other. The pigment 20 a further has a wet deposited n _h outer protective oxide layer 200.

  The method for producing a multilayer laminate disclosed herein may be any method or process known to those skilled in the art or not yet known. Typical methods include wet methods such as sol-gel processing, layer-by-layer processing, spin coating, and the like. Other known dry methods include chemical vapor deposition and physical vapor deposition processes such as sputtering, electron beam evaporation, and the like.

  The multilayer laminates disclosed herein can be used for almost any color coating, such as paint pigments, thin films coated on the surface, and the like. In addition, the pigments shown in FIGS. 16 and 18 exhibit omnidirectional structural color characteristics as shown in FIGS.

  Examples of weathering omnidirectional structural color pigments and manufacturing processes for making such pigments are discussed below to better teach the present invention, but not to limit its scope in any way. .

<Procedure 1> Five-layer pigment coated with _two layers of ZrO _Two grams of five-layer pigment were suspended in 30 ml of ethanol in a 100 ml round bottom flask and stirred at 500 rpm at room temperature. 2.75 ml of a solution of zirconium butoxide (80% in 1-butanol) was dissolved in 10 ml of ethanol and titrated at a constant rate for 1 hour. At the same time, 1 ml of deionized water diluted in 3 ml of ethanol was weighed and added. After titration, the suspension was stirred for an additional 15 minutes. This mixture is filtered, washed with ethanol followed by isopropanol, and dried at 100 ° C. for 24 hours, or alternatively annealed further at 200 ° C. for 24 hours to finally have the structure shown in FIG. A five-layer pigment was obtained. If necessary, further annealing at a higher temperature may be performed.

<Procedure 2> Five-layer pigment covered with _two layers of TiO ₂ grams of five-layer pigment was suspended in 30 ml IPA in a 100 ml round bottom flask and stirred at 40 ° C. Then, a solution of 2.5 ml of titanium ethoxide (97%) dissolved in 20 ml of IPA was titrated at a constant rate for 2.5 hours. At the same time, 2.5 ml of deionized water diluted in 4 ml of IPA was quantitatively added. After titration, the suspension was stirred for an additional 30 minutes. This mixture is cooled to room temperature, filtered, washed with IPA, dried at 100 ° C. for 24 hours, or alternatively annealed further at 200 ° C. for 24 hours to finally have the structure shown in FIG. A layer pigment was obtained. If necessary, further annealing at a higher temperature may be performed.

  A summary of the coating, the procedure for making the coating, the coating thickness, the coating thickness uniformity, and the photodegradation reactivity is shown in Table 3 below.

  From the above, Table 4 provides an inventory of various oxide layers, substrates that can be coated, and coating thicknesses included in the present teachings.

  In addition to the above, the omnidirectional structural color pigment having a protective coating may be subjected to an organosilane surface treatment. For example, in one exemplary organosilane process, 0.5 g of pigment coated with one or more of the above protective layers is added to 10 ml of pH about 5.0 (diluted acetic acid solution) in a 100 ml round bottom flask. Suspended in EtOH / water (4: 1) solution. The slurry was sonicated for 20 seconds and stirred at 500 rpm for 15 minutes. Next, 0.1 to 0.5 vol% of organosilane agent was added to the slurry, and the solution was further stirred at 500 rpm for 2 hours. The slurry was centrifuged using deionized water or filtered, and the residual pigment was redispersed in 10 ml of EtOH / water (4: 1) solution. The pigment-EtOH / water slurry was heated to 65 ° C. under reflux and stirred at 500 rpm for 30 minutes. The slurry was then centrifuged using deionized water followed by IPA or filtered to obtain a cake of pigment particles. Finally, the cake was dried at 100 ° C. for 12 hours. If necessary, further annealing at a higher temperature may be performed.

  The organosilane process can use any organosilane coupling agent known to those skilled in the art, such as N- (2-aminoethyl) -3-aminopropyltrimethoxysilane (APTMS), N- [3- (Trimethoxysilyl) propyl] ethylenediamine 3-mesoalkyloxypropyltrimethoxy-silane (MAPTMS), N- [2 (vinylbenzylamino) -ethyl] -3-aminopropyltrimethoxysilane, 3-glycid-oxypropyltri Includes methoxysilane and the like.

  The above examples and embodiments are for illustrative purposes only, and variations, modifications, and the like apparent to those skilled in the art are within the scope of the present invention. Accordingly, the scope of the invention is defined by the claims and all equivalents thereof.

The present invention further includes the following embodiments:
1. Reflective core layer,
A dry deposited high refractive index (n _h ) dielectric layer extending across the reflective core layer;
Have a multilayer laminate having the n _h airlaid absorbent layer extending over the dielectric layer, and wet n _h outer oxide layer extending over the absorber layer,
The multilayer stack is less than 300 nm when the multilayer stack is exposed to broadband electromagnetic radiation and observed from an angle between 0 ° and 45 ° with respect to a direction perpendicular to the outer surface of the multilayer stack. Having a reflection band with a given half width (FWHM) and a given color shift less than 30 °;
Hybrid omnidirectional structural color pigment.
2. The reflective core layer is a metal core reflector layer having a thickness of 30 nm to 200 nm, and at least one selected from the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof. 2. The hybrid omnidirectional structural color pigment according to 1 above, which is a metal material selected more.
3. The airlaid _{n h} dielectric _{layer, CeO 2, Nb 2 O 5} , SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and dielectric material selected from at least one of the group consisting of ZrO ₂ The hybrid omnidirectional structural color pigment as described in 2 above.
4). The airlaid _{n h} dielectric layer has a thickness of 0.1QW~4.0QW for desired adjustment wavelength, hybrid omnidirectional structural color pigment according to the 3.
5. 5. The dry deposition absorber layer is an absorber material selected from at least one selected from the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, and Fe ₂ O _3. Hybrid omnidirectional structural color pigment.
6). 6. The hybrid omnidirectional structural color pigment according to 5 above, wherein the dry absorber layer has a thickness of 2 nm to 30 nm.
7). The wetlaid _{n h} outer oxide layer _is a _{CeO 2, Nb 2 O 5,} SnO 2, TiO 2, ZnO, and oxide selected from at least one of the group consisting of ZrO _2, the 6 The described hybrid omnidirectional structural color pigment.
8). The wetlaid _{n h} outer oxide layer has a thickness between 5 nm to 200 nm, the hybrid omnidirectional structural color pigment according to the 7.
9. The dry deposited _nh dielectric layer is a pair of _nh dielectric layers between which the reflective core layer extends, and the dry deposited absorber layer is a pair of _nh dielectrics between them. 9. The hybrid omnidirectional of claim 8, wherein the wet-deposited _nh outer oxide layer extends over an outer surface of the pair of dry-deposited absorber layers, wherein the layer is a pair of dry-deposited absorber layers that extend. Structural color pigment.
10. The hybrid omnidirectional structural color pigment according to 9, wherein the multilayer laminate has a thickness of less than 2.0 μm.
11. 10. The hybrid omnidirectional structural color pigment as described in 9 above, wherein the multilayer laminate has a thickness of less than 1.5 μm.
12 12. The hybrid omnidirectional structural color pigment as described in 11 above, wherein the multilayer laminate is less than 10 layers.
13. 13. The hybrid omnidirectional structural color pigment as described in 12 above, wherein the multilayer laminate is less than 8 layers.
14 Providing a reflective core layer,
Dry depositing a high refractive index (n _h ) dielectric layer extending across the reflector core layer;
to dry depositing the absorber layer extending over n _h dielectric layer comprises fabricating a multilayer stack and n _h oxide layer extending over the absorber layer by wet deposition,
The multilayer stack is less than 300 nm when the multilayer stack is exposed to broadband electromagnetic radiation and observed from an angle between 0 ° and 45 ° with respect to the normal direction of the outer surface of the multilayer stack. A reflection band having a full width at half maximum (FWHM) and a given color shift less than 30 °;
Method for producing omnidirectional structural color pigment.
15. The reflective core layer has a thickness of 30 nm to 200 nm made of a metal material selected from at least one of the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof. A metal core reflector layer,
The airlaid _{n h} dielectric layer has a thickness between 0.1QW~4.0QW the desired adjustment wavelength, and _{CeO 2, Nb 2 O 5,} SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and is made from a dielectric material selected from at least one of the group consisting of ZrO _2, the method described in the 14.
16. The dry absorber layer has a thickness of 2 nm to 30 nm and is selected from at least one selected from the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, and Fe ₂ O ₃ 16. The method according to 15 above, which is made from a body material.
17. Wetlaid _{n h} outer oxide layer has a thickness of 5 nm to 200 nm, and _{CeO 2, Nb 2 O 5,} SnO 2, TiO 2, ZnO, and at least selected from one from the group consisting of ZrO ₂ 17. The method according to 16 above, which is an oxide.
18. 18. The method of claim 17, wherein the multilayer stack is less than 10 layers.
19. 18. The method of 17, wherein the multilayer stack is less than 8 layers.
20. The method of claim 17, wherein the multilayer stack has a total thickness of less than 2.0 μm.

Claims (20)

Reflective center layer,
A dry deposited high refractive index (n _h ) dielectric layer extending over the reflective core layer;
Have a multilayer laminate having the n _h airlaid absorbent layer extending over the dielectric layer, and wet n _h outer oxide layer extending over the absorber layer,
Where the multilayer stack is less than 300 nm when the multilayer stack is exposed to broadband electromagnetic radiation and observed from an angle between 0 ° and 45 ° with respect to the vertical direction of the outer surface of the multilayer stack. Having a reflection band with a given half width (FWHM) and a given color shift less than 30 °;
Hybrid omnidirectional structural color pigment.   The reflective core layer is a metal core reflector layer having a thickness of 30 nm to 200 nm, and at least one selected from the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof. The hybrid omnidirectional structural color pigment according to claim 1, which is a metal material selected from the above. The airlaid _{n h} dielectric _{layer, CeO 2, Nb 2 O 5} , SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and dielectric material selected from at least one of the group consisting of ZrO ₂ The hybrid omnidirectional structural color pigment according to claim 2, wherein   The hybrid omnidirectional structural color pigment of claim 3, wherein the dry deposited nh dielectric layer has a thickness of 0.1QW to 4.0QW for a desired tuning wavelength. The dry deposition absorber layer is an absorber material selected from at least one of the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, and Fe ₂ O _3. The described hybrid omnidirectional structural color pigment.   The hybrid omnidirectional structural color pigment according to claim 5, wherein the dry absorber layer has a thickness of 2 nm to 30 nm. The wetlaid _{n h} outer oxide layer _is a _{CeO 2, Nb 2 O 5,} SnO 2, TiO 2, ZnO, and oxide is at least selected from one from the group consisting of ZrO _2, in claim 6 The described hybrid omnidirectional structural color pigment. The wetlaid _{n h} outer oxide layer has a thickness between 5 nm to 200 nm, the hybrid omnidirectional structural color pigment according to claim 7. The dry deposited _nh dielectric layer is a pair of _nh dielectric layers between which the reflective core layer extends, and the dry deposited absorber layer is a pair of _nh dielectrics between them. 9. The hybrid of claim 8, wherein the hybrid is a pair of dry deposition absorber layers with a body layer extending and the wet deposition _nh outer oxide layer extends over an outer surface of the pair of dry deposition absorber layers. Omnidirectional structural color pigment.   The hybrid omnidirectional structural color pigment according to claim 9, wherein the multilayer laminate has a thickness of less than 2.0 μm.   The hybrid omnidirectional structural color pigment according to claim 10, wherein the multilayer laminate has a thickness of less than 1.5 m.   The hybrid omnidirectional structural color pigment of claim 11, wherein the multilayer laminate is less than 10 layers.   The hybrid omnidirectional structural color pigment of claim 12, wherein the multilayer laminate is less than 8 layers. Providing a reflective core layer,
Dry depositing a high refractive index (n _h ) dielectric layer extending across the reflective core layer;
to dry depositing the absorber layer extending over n _h dielectric layer comprises fabricating a multilayer stack and n _h oxide layer extending over the absorber layer by wet deposition,
The multilayer stack is less than 300 nm when the multilayer stack is exposed to broadband electromagnetic radiation and observed from an angle between 0 ° and 45 ° with respect to the normal direction of the outer surface of the multilayer stack. A reflection band having a full width at half maximum (FWHM) and a given color shift less than 30 °;
Method for producing omnidirectional structural color pigment. The reflective core layer is made of a metal material selected from at least one of the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and alloys thereof, and has a thickness of 30 nm to 200 nm. A metal core reflector layer having
The airlaid _{n h} dielectric layer has a thickness between 0.1QW~4.0QW for desired adjustment wavelength, and _{CeO 2, Nb 2 O 5,} SiN, SnO 2, SnS, TiO 2, ZnO, ZnS, and is made from a dielectric material selected from at least one of the group consisting of ZrO _2, the method of claim 14. The dry absorber layer has a thickness of 2 nm to 30 nm and is selected from at least one selected from the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, and Fe ₂ O ₃ 16. A method according to claim 15 made from body material. Wetlaid _{n h} outer oxide layer has a thickness of 5 nm to 200 nm, and _{CeO 2, Nb 2 O 5,} SnO 2, TiO 2, ZnO, and at least selected from one from the group consisting of ZrO ₂ The method according to claim 16, which is an oxide.   The method of claim 17, wherein the multilayer stack is less than 10 layers.   The method of claim 18, wherein the multilayer stack is less than 8 layers.   The method of claim 19, wherein the multilayer stack has a total thickness of less than 2.0 μm.