JP7036886B2 - Durable hybrid omnidirectional structural color pigment for external coating - Google Patents

Description

The present invention has a multi-layered structure with a protective coating and, in particular, a protective coating that exhibits minimal or unrecognizable color shift when exposed to wideband electromagnetic radiation and viewed from different angles. Regarding a hybrid multi-layer laminated structure.

<Cross-reference to related inventions>
This application is a partial continuation of US Patent Application No. 14 / 471,834 filed on August 28, 2014, which is one of US Patent Application Nos. 14 / 460,511 filed on August 15, 2014. This is a partial continuation application, which is a partial continuation application of US Patent Application No. 14 / 242,429 filed on April 1, 2014, which is a US patent application 14 / filed on December 23, 2013. This is a partial continuation application of No. 138,499, which is a partial continuation application of US Patent Application No. 13 / 913,402 filed on June 8, 2013, which was filed on February 6, 2013. Is a partial continuation application of US Patent Application No. 13 / 760,699, which is a partial continuation application of No. 13 / 571,071 filed on August 10, 2012, which is February 2011. This is a partial continuation application of US Patent Application No. 13 / 021,730 filed on the 5th, which is a partial continuation application of US Patent Application No. 12 / 793, 772 filed on June 4, 2010 (US Patent No. 1). 8,736,959), which is a partial continuation application of US Patent Application No. 12 / 388,395 filed on February 18, 2009 (US Patent No. 8,749,881). Is a partial continuation application of US Patent Application No. 11 / 837,529 filed on August 12, 2007 (US Patent Application No. 7,903,339). US Patent Application No. 13 / 913,402 filed June 8, 2013 is a partial continuation application of No. 13/014,398 filed January 26, 2011, which is June 4, 2010. This is a partial continuation application of application No. 12 / 793, 772, which is a partial continuation application of No. 12 / 686,861 (US Pat. No. 8,593,728) filed on January 13, 2010. Yes, this is a partial continuation of application 12 / 389,256 (US Pat. No. 8,329,247) filed February 19, 2009, all of which are incorporated by reference in their entirety. Will be done.

Pigments made from multi-layer structures are known. In addition, pigments that exhibit or bring about highly colored omnidirectional structural colors are further known. However, the pigments of the prior art required as many as 39 thin film layers in order to obtain the desired color characteristics.

It should be understood that the cost of producing thin film multilayer pigments is proportional to the number of layers required. Therefore, the cost of producing a highly colored omnidirectional structural color using a multilayer laminate of dielectric materials can be very high. Therefore, a highly colored omnidirectional structural color that requires a minimal thin film layer is desirable.

In addition to the above, it should be understood that pigments may fade, discolor, etc. when exposed to sunlight, and especially ultraviolet light. Therefore, there is a further demand for weather resistant, highly saturated omnidirectional structural color pigments.

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

The pigment has the form of a multilayer laminate that reflects a reflection band with a given full width at half maximum (FWHM) of less than 300 nm, as well as what is also referred to herein as a multilayer thin film. In addition, this reflection band has a given color shift of less than 30 ° in the a ^* b ^* color map using CIELAB when exposed to wideband electromagnetic radiation and viewed from an angle of 0 ° to 45 °. ..

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

The 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 Al, Ag, Pt, Cr, Cu, Zn, Au, Sn, and at least one of these alloys.

The dry deposited nh dielectric layer is at least one of CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , _SnS , TiO ₂ , 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 deposited nh dielectric layer has a thickness between _0.1QW and 4.0QW for the desired adjustment wavelength, which is the central wavelength of the desired color reflection band. Is. The dry sediment absorber layer is made of at least one of Cr, Cu, Au, Sn, alloys thereof, amorphous Si, Fe ₂ O ₃ and the like, with a thickness between 2 nm and 30 nm. May have The wet deposit _nh external oxide layer is made from at least one of CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ and has a thickness between 5 nm and 200 nm. You can do it.

In some examples, the multilayer has a central reflector core layer and a pair of dry deposited _nh dielectric layers arranged opposite to each other and bonded to the reflective core layer. In addition, the pair of absorber layers may be disposed facing each other and bonded to the pair of dry deposited _nh dielectric layers. Further, the wet deposit _nh external oxide layer may extend over the outer surface 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 less than 10 layers in total, and in some examples may have less than 8 layers in total.

Further provided is a method for producing an omnidirectional structural color pigment. The method comprises supplying the reflective core layer and dry depositing the _nh dielectric layer extending over the reflective core layer to produce the multilayer laminate described above. In addition, this method involves dry deposition of an absorber layer extending over the _nh dielectric layer and wet deposition of an external _nh oxide layer extending over the absorber layer.

FIG. 1 is a schematic diagram of an omnidirectional structural color multilayer laminate made of a dielectric layer, a selective absorbent 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 with respect to the square of the absolute value of the electric field (| E | ² ). It is a graph diagram. FIG. 3 is a schematic view of a dielectric layer extending over a substrate or reflector layer and exposed to electromagnetic radiation from an angle θ with respect to the direction perpendicular to 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 arranged at a zero or near zero electric field point with respect to an incident EMR having a wavelength of 434 nm in the ZnS dielectric layer. FIG. 5 shows the reflection of a multilayer laminate without a Cr absorber layer (eg, FIG. 2A) and a multilayer laminate with a Cr absorber layer (eg, FIG. 4) with respect to percent reflectance when exposed to white light. It is a graph display of the EMR wavelength. FIG. 6A is a graph of the first and second harmonics represented by the ZnS dielectric layer (eg, FIG. 2A) extending over the Al reflector layer. FIG. 6B shows a ZnS dielectric layer extending over the Al reflector layer and a Cr absorber layer arranged in the ZnS dielectric layer so that the second harmonic as shown in FIG. 6A is absorbed. It is a graph of the reflection EMR wavelength with respect to the reflectance percent of the multilayer laminate having. FIG. 6C shows a ZnS dielectric layer extending over the Al reflector layer and a Cr absorber layer arranged in the ZnS dielectric layer so that the first harmonic as shown in FIG. 6A is absorbed. It is a graph of the reflection EMR wavelength with respect to the reflectance percent of the multilayer laminate having. FIG. 7A is a graph showing the thickness of the dielectric layer with respect to the square of the electric field, which represents the electric field angle dependence of the Cr absorber layer when exposed to incident light from 0 ° and 45 °. FIG. 7B shows the reflection of white light on the percent absorption rate by the Cr absorber layer when exposed to white light from angles 0 ° and 45 ° with respect to the vertical direction of the outer surface (0 ° is perpendicular to the surface). It is a graph of the EMR wavelength. FIG. 8A is a schematic diagram of a red omnidirectional structural color multilayer laminate based on an embodiment disclosed herein. FIG. 8B is a graph of the reflected EMR wavelength with respect to the percent absorption rate of the Cu absorber layer shown in FIG. 8A when white light is exposed to the multilayer laminate shown in FIG. 10A at incident angles of 0 ° and 45 °. Is. FIG. 9 is a graph comparison of calculation / simulation data and experimental data for reflected EMR wavelengths to prove the concept of a red omnidirectional structural color multilayer laminate exposed to white light at an incident angle of 0 °. FIG. 10 is a graph of wavelengths relative to percent reflectance for an omnidirectional structural color multilayer laminate according to an embodiment disclosed herein. FIG. 11 is a graph of wavelengths relative to percent reflectance for an omnidirectional structural color multilayer laminate according to an embodiment disclosed herein. FIG. 12 is a graph of percent reflectance to wavelength for an omnidirectional structural color multilayer laminate according to an embodiment disclosed herein. FIG. 13 is a graph of percent reflectance with respect to wavelength for an omnidirectional structural color multilayer laminate based on an embodiment disclosed herein. FIG. 14 compares the saturation and color shift of a conventional paint and a paint made from a pigment according to an embodiment disclosed herein (sample (b)), using CIELAB a ^* b. ^* A part of the graph display of the color map. FIG. 15 is a schematic diagram of an omnidirectional structural color multilayer laminate based on an embodiment disclosed herein. FIG. 16 is a schematic representation of a five-layer omnidirectional structural color pigment with a protective coating, based on an embodiment disclosed herein. FIG. 17 is a schematic representation of a protective coating with two or more layers according to an embodiment disclosed herein. FIG. 18 is a schematic diagram of an omnidirectional structural color multilayer laminate based on an embodiment disclosed herein. FIG. 19 is a schematic representation of a 7-layer omnidirectional structural color pigment with a protective coating, based on an embodiment disclosed herein.

Provided is an omnidirectional structural color pigment. This omnidirectional structural color reflects a narrow band of electromagnetic radiation in the visible spectrum and is a small or unrecognizable color when the multilayer is viewed by the human eye from an angle between 0 ° and 45 °. It has the form of a multi-layer laminate (further referred to herein as a "multi-layer thin film") with a shift. More technically, this multilayer laminate reflects a narrow band of visible electromagnetic radiation smaller 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 less than 30 °.

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

Another criterion for color shift is the shift of the central wavelength in the narrow reflection band. From this point of view, when the multilayer stack is exposed to wideband 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, the reflected visible light has a narrow band. The center wavelength shifts to less than 50 nm, preferably less than 40 nm, more preferably less than 30 nm. Further, the multilayer stack may or may not have a separate reflection band of electromagnetic radiation in the UV and / or IR regions.

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

The multi-layer laminate includes a reflector core layer in which a first layer and a second layer extend, and the reflector core layer is a metal such as Al, Ag, Pt, Cr, Cu, Zn, Au. , Sn, alloys of these, and the like. The reflector core layer usually has a thickness between 30 nm and 200 nm.

The first layer is made of _nh dielectric material and the second layer is made of absorbent material. The nh dielectric material may include, but is not limited to, CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , _SnS , TiO ₂ , ZnO, ZnS, and ZrO ₂ . The absorbent material is a selective absorbent material such as Cu, Au, Zn, Sn, alloys thereof, and the like, or alternative, colored dielectric materials such as Fe ₂ O ₃ , Cu ₂ O, these. Combinations of, and the same kind may be included. 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, a combination or alloy thereof. And may be of the same type. The external protective layer may include, but is not limited to, CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ .

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

The multilayer stack may have a narrow reflection band of electromagnetic radiation having a symmetrical peak shape in the visible spectrum. Alternatively, the reflected narrow band of electromagnetic radiation in the visible spectrum may be adjacent to the UV region, whereby part of the reflected narrow band of electromagnetic radiation, such as the UV portion, is invisible to the human eye. In another alternative, the reflection band of electromagnetic radiation may have a portion in the IR region, which makes the IR portion invisible to the human eye.

Whether the reflection band of electromagnetic radiation within the visible region is in contact with the UV region, IR region, or has bilaterally symmetric peaks in the visible spectrum, the multilayer stacks disclosed herein are visible. It has a narrow reflection band of electromagnetic radiation in the spectrum, which is low, small or has unrecognizable color shift. The low or unrecognizable color shift may be in the form of a small shift 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 small shift at the UV or IR side of the reflection band of electromagnetic radiation in contact with the IR or UV regions, respectively. Such small shifts at the center wavelength, UV side edges, and / or IR side edges when observing the multilayer stack from an angle between 0 ° and 45 ° with respect to the vertical direction of the outer surface of the multilayer. Is usually less than 50 nm, less than 40 nm in some examples and less than 30 nm in others. This low or unrecognizable color shift may further be in the form of a small color shift on the a ^* b ^* color map using the CIELAB color space. For example, in one example, the color shift for a multilayer laminate is less than 30 °, preferably less than 25 °, even 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 in the form of a multilayer laminate may be in the form of a plurality of pigment particles having an external protective coating, eg, a weathering coating. The external protective coating may include one or more _nh oxide layers that reduce the relative photocatalytic reaction of the pigment particles. In one example, the external protective coating comprises 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, that is, an oxide layer that is a combination of two oxides.

Methods for producing omnidirectional structural color pigments may or may not include 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 for producing these pigments are discussed later herein.

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

Designs as shown in FIG. 1 correspond to different techniques for designing and manufacturing the desired multilayer laminate. 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 diagram of a ZnS dielectric layer extending over the Al reflector core layer. The ZnS dielectric layer has a total thickness of 143 nm and has zero or near zero energy points at 77 nm for incident electromagnetic radiation having a wavelength of 500 nm. In other words, for incident electromagnetic radiation (EMR) with a wavelength of 500 nm, the ZnS dielectric layer represents a zero or near 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 a zero or near zero electric field 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. It has a non-zero electric field.

For the calculation of zero or near zero electric field points, FIG. 3 shows the total thickness "D", the incremental thickness "d", and the index of refraction "n" on the substrate or core layer 2 having the index of refraction n _s . Represents the dielectric layer 4 having the above. The incident light hits the outer surface 5 of the dielectric layer 4 at an angle θ with respect to the line 6 perpendicular to the outer surface 5 and is reflected from the outer surface 5 at the same angle θ. The 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 hits the surface 3 of the base material layer 2 at an angle θ _s .

また、ｐ偏光について：

のように表現することができ、ここで、ｋ＝２π／λであり、λは反射されるべき所望の波長である。さらに、α＝_ｎｓｉｎθ_ｓであり、ここで「ｓ」は、図５において基材に対応し、また

はｚの関数である、この層の誘電率である。
したがって、ｓ偏光について、

及びｐ偏光について、

である。 When z = d, θ _s = θ _F and the energy / electric field (E) can be expressed as E (z) for one dielectric layer. From Maxwell's equations, about s polarization:

Also, about p-polarization:

Where k = 2π / λ, where λ is the desired wavelength to be reflected. Further, α = _n sin θ _s , where “s” corresponds to the substrate in FIG.

Is the permittivity of this layer, which is a function of z.
Therefore, regarding s polarization,

And about p-polarization

Is.

当然に、「ｉ」は－１の平方根である。境界条件

、及び下記の関係を利用して：
ｓ偏光について、ｑ_ｓ＝ｎ_ｓｃｏｓθ_ｓ （６）
ｐ偏光について、ｑ_ｓ＝ｎ_ｓ／ｃｏｓθ_ｓ （７）
ｓ偏光について、ｑ_Ｆ＝ｎｃｏｓθ_Ｆ （８）
ｐ偏光について、ｑ_Ｆ＝ｎ／ｃｏｓθ_Ｆ （９）
φ＝ｋ・ｎ・ｄｃｏｓ（θ_Ｆ） （１０）
ｕ（ｚ）及びｖ（ｚ）は、以下のように表現することができる：

及び

ゆえに、ｓ偏光について、

を用いて：

及び、ｐ偏光について：

ここで、

及び

It should be understood that the change in the electric field of the dielectric layer 4 in the Z-axis direction can be estimated by calculating the unknown parameters u (z) and v (z) which can be shown as follows.

Naturally, "i" is the square root of -1. boundary condition

, And the following relationships:
For s polarization, q _s = n _s cos θ _s (6)
For p-polarization, q _s = n _s / cos θ _s (7)
For s polarization, q _F = ncos θ _F (8)
For p-polarization, q _F = n / cos θ _F (9)
φ = k · n · dcos (θ _F ) (10)
u (z) and v (z) can be expressed as:

as well as

Therefore, about s polarization,

Using:

And about p-polarization:

here,

as well as

これは、厚さ「ｄ」、例えば誘電体層中の電場がゼロになる位置、又は場所について解くことができる。 Thus, under the simple condition of θ _F = 0 or vertical incident, φ = k · n · d and α = 0:
About s polarization | E (d) | ² = About p polarization

This can be solved for a thickness "d", eg, where or where the electric field in the dielectric layer becomes zero.

With reference to FIG. 4, Equation 19 was used to calculate zero or near zero electric field points in the ZnS dielectric layer shown in FIG. 2A when exposed to EMR with a wavelength of 434 nm. A zero or near zero electric field point was calculated to be 70 nm (as opposed to 77 nm for a 500 nm wavelength). In addition, a Cr absorber layer with a thickness of 15 nm 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. In such an original structure, light having a wavelength of 434 nm passes 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 near zero electric field for light having a wavelength of 434 nm, whereby light at 434 nm passes through this boundary. However, the Cr-ZnS boundary does not have a zero or near zero electric field point for light having no wavelength of 434 nm, whereby 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 appreciated 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, such as 434 +/- 10 nm, still provides a vivid structural color to the human eye.

The results of the Cr absorber layer in the multilayer stack of FIG. 4 are shown in FIG. 5, where the percent reflectance with respect to the reflected EMR wavelength is shown. As shown by the dotted line corresponding to the ZnS dielectric layer shown in FIG. 4, which does not have a Cr absorber layer, there is a narrow reflection peak at about 400 nm, but 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 laminate from exhibiting structural color.

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

By designing or setting the thickness of the ZnS dielectric layer for the omnidirectional structure shown in FIG. 4, only the first harmonic of the reflected light can be brought about. It should be understood that this is sufficient to obtain a "blue" color, however, further consideration is needed to create a "red" color. For example, angle-independent adjustment for red is difficult because it requires a thicker dielectric layer, which results in a high harmonic design, i.e., the second and desired third harmonics. The waves are inevitable. Moreover, the dark brown color space is very narrow. Therefore, the red multilayer laminate has a high angular change.

To overcome this high angular change in red, the present application discloses a design / structure that results in a unique, novel, angle-independent red. For example, FIG. 6A shows a dielectric exhibiting first and second harmonics with respect to incident white light when the outer surface of the dielectric layer is observed from angles 0 ° and 45 ° with respect to the vertical direction of the outer surface. Represents a layer. As shown in this graph display, low angular dependence (small Δλ _c ) is provided by the thickness of the dielectric layer, but such multilayers are blue (first harmonic) and red. It has a combination of (second harmonics) and is therefore not suitable for the desired "red only" color. Therefore, this theory / structure has been developed to utilize the absorber layer to absorb a group of unwanted harmonics. FIG. 6A shows the position of the center wavelength (λ _c ) of the reflection band of a given reflection peak, and the dispersion or shift (Δλ _c ) of this center wavelength when the sample is viewed from an angle between 0 ° and 45 °. ) Is further shown.

With reference to FIG. 6B, the second harmonic shown in FIG. 6A is absorbed by the Cr absorber layer at the appropriate dielectric layer thickness (eg 72 nm), resulting in a vibrant blue color. Further, FIG. 6C shows that the absorption of the first harmonic at different dielectric layer thicknesses (eg 125 nm) depending on the Cr absorber layer results in a red color. However, FIG. 6C further shows that the use of the Cr absorber layer can result in a higher angle dependence of this multilayer laminate than desired, i.e., greater than the desired Δλ _c .

The relatively large shift of λ _c for red compared to blue is that this dark red color space is very narrow and the Cr absorber layer absorbs the color corresponding to the non-zero or near-zero electric field. That is, it should be understood by the fact that it does not absorb light when this electric field is zero or near zero. Therefore, FIG. 7A shows that this zero or near zero electric field point with respect to the light wavelength differs depending on the angle of incidence. Such factors result in angle-independent absorptivity shown in FIG. 7B, i.e., differences in absorptivity curves at 0 ° and 45 °. Therefore, in order to further improve the design of the multilayer 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 laminate in which a Cu absorber layer extends over the ZnS layer instead of the Cr absorber layer. The results of using such "colored" or "selective" absorber layers are shown in FIG. 8B, which is a more "colored" or 45 ° absorption rate line of the multilayer laminate shown in FIG. 8A. It represents a "strict" grouping. Therefore, comparisons between FIGS. 8B and 7B show that by using the selective absorber layer instead of the non-selective absorber layer, there is a significant improvement in the angle-independent absorptivity. ing.

Based on the above, a multi-layered laminate structure was designed and manufactured to prove the concept. In addition, the calculation / simulation results for the sample to prove the concept and the actual experimental data were compared. In particular, as also shown in the graph plot of FIG. 9, a clear red color is obtained (wavelengths larger than 700 nm are usually invisible to the human eye), and experiments obtained from calculations / simulations and actual samples. Very good agreement was obtained with the light data of. In other words, the calculation / simulation can be used to simulate or simulate the results of a multi-layer laminate design of one or more embodiments of the invention and / or known multi-layer laminates.

An inventory of samples of the multilayer laminate simulated and / or actually produced is provided in Table 1 below. As shown in the table, the design of the invention disclosed herein comprises at least five different layered structures. In addition, this sample was simulated and / or made from a large area of material. The sample exhibited 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.

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

This sharp increase in reflectance provided by this omnidirectional reflector is characterized by the IR side edge of each curve extending from the low reflectance portion at wavelengths above 500 nm to the high reflectance portion, eg> 70% portion. Be done. The linear portion 200 on the IR end side is tilted at an angle (β) greater than 60 ° with respect to the x-axis and has a length L of about 50 and a tilt of 1.2 on the reflectance axis. In one example, the linear portion is tilted at an angle greater than 70 ° with respect to the x-axis, while in other examples β is greater than 75 °. In addition, the reflection band has a visible FWHM smaller than 200 nm, in some cases a visible FWHM smaller than 150 nm and in another example a visible FWHM smaller than 100 nm. In addition, the central wavelength λ _c of the visible reflection band as shown in FIG. 10 is defined as a wavelength 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" refers to the width of the reflection band between the IR end of this curve and beyond this the end of the UV spectral region where the reflections supplied by the omnidirectional reflector are invisible to the human eye. Is mentioned. As such, the designs and multilayers of the invention disclosed herein use invisible UV moieties of electromagnetic radiation to provide a vivid 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 reflectors disclosed herein have a narrow band of reflected visible light. To provide, the invisible UV portion of the electromagnetic radiation spectrum is utilized.

Referring to FIG. 11, the overall symmetrical reflection bands provided when the multilayer laminate according to the embodiment of the present invention is observed from 0 ° and 45 ° are shown. As shown in the figure, the reflection band provided by the multilayer stack has a center wavelength λ _c (0 °) when viewed from 0 ° and a center wavelength λ _c (45 °) when viewed from 45 °. Further, when the multilayer laminate is viewed from an angle between 0 ° and 45 °, the shift of the center wavelength is smaller than 50 nm, that is, Δλ _c (0-45 ^o ) <50 nm. In addition, the FWHM of the 0 ° reflection band and the 45 ° reflection band is smaller than 200 nm.

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

This sharp increase in reflectance provided by this omnidirectional reflector is characterized by the UV side edge of each curve extending from the low reflectance portion at wavelengths smaller than 550 nm to the high reflectance portion, eg> 70% portion. Be done. The straight portion 200 on the UV end side is tilted at an angle (β) greater than 60 ° with respect to the x-axis and has a length L of about 40 and a tilt of 1.4 on the reflectance axis. In one example, the linear portion is tilted at an angle greater than 70 ° with respect to the x-axis, while in other examples β is greater than 75 °. In addition, the reflection band has a visible FWHM smaller than 200 nm, in some cases a visible FWHM smaller than 150 nm and in another example a visible FWHM smaller than 100 nm. In addition, the central wavelength λ _c of this visible reflection band represented in FIG. 12 is defined as a wavelength 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" refers to the width of the reflection band between the UV end of this curve and beyond this the end of the IR spectral region where the reflections supplied by the omnidirectional reflector are invisible to the human eye. Please understand that it refers to. As such, the designs and multilayers of the invention disclosed herein use an invisible IR portion of electromagnetic radiation to provide a vivid structural color. In other words, despite the fact that the reflector reflects a wider band of electromagnetic radiation extending into the IR region, the omnidirectional reflectors disclosed herein provide a narrow band of reflected visible light. In order to do so, the invisible IR part of the electromagnetic radiation spectrum is used.

Referring to FIG. 13, a plot of reflectance percent vs. wavelength of another 7-layer design omnidirectional reflector when exposed to white light from 0 ° and 45 ° angles to the surface of this reflector. Shows. In addition, it provides a definition or evaluation of the omnidirectional properties provided by the omnidirectional reflectors disclosed herein. In particular, also when the reflection band provided by the reflectors of the present invention is maximal, i.e. having peaks as shown in the figure, each curve exhibits or experiences maximum reflectance at the center wavelength (λ _c ). Have. The term maximum reflected wavelength is also used as λ _c .

As shown in FIG. 13, the surface of the omnidirectional reflector is tilted at a 45 ° angle (λ _c (45 ^o )), for example, an angle at which the outer surface is tilted at 45 ° with respect to the eyes of the viewer. When observed, there is a shift or displacement of λ _c as compared to an angle of 0 ° (λ _c (0 ^o )), eg, when observing the surface from a direction perpendicular to the surface. This shift of λ _c (Δλ _c ) results in an omnidirectional characteristic measure of the omnidirectional reflector. Of course, when there is no shift, that is, no shift at all, it is a perfect omnidirectional reflector. However, the omnidirectional reflector disclosed herein appears to the human eye as if the surface color of the reflector does not change, so from a practical point of view the reflector is omnidirectional. , Δλ _c smaller than 50 nm can be provided. In some examples, the omnidirectional reflectors disclosed herein can provide Δλ _c less than 40 nm, in other examples can provide Δλ _c less than 30 nm, and yet another example. In, Δλ _c of less than 20 nm can be provided, and in yet another example, Δλ _c of less than 15 nm can be provided. Such a shift of _Δλc can be measured by plotting the wavelength to the actual reflectance of the reflector and / or alternatively, if the material and layer thickness are known, by modeling the reflector. ..

Another definition or characteristic of the omnidirectional characteristic of the reflector can be measured by an end-side shift of a given angular reflection band. For example, with reference to FIG. 10, the omnidirectional reflector was observed from 0 ° compared to the IR side edge ( _SIR (45 ^o )) for the reflectance when the same reflector was observed from 45 °. The shift or displacement (ΔS _IR ) of the IR side edge ( _SIR (0 ^o )) with respect to the reflectance at the time provides a measure of the omnidirectional characteristic of the omnidirectional reflector. In addition, if Δλ _c is used, eg, for a reflector that provides a reflectance band similar to that shown in FIG. 10 or 12, i.e. for a reflection band that extends into the UV or IR region of the EMR, ΔS. It is preferable to use _IR as an omnidirectional measure. It should be understood that the shift at the IR side edge (ΔS _IR ) can be measured and / or done in a visible FWHM.

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

Of course, zero shift, i.e. no shift at all (ΔS _i = 0 nm; i = IR, UV) characterizes a perfect omnidirectional reflector. However, the omnidirectional reflectors disclosed herein can result in _ΔSLs smaller than 50 nm, which makes the surface color of the reflector appear unchanged to the human eye and is therefore a practical point of view. From now on, this reflector is omnidirectional. In some examples, the omnidirectional reflectors disclosed herein can result in ΔS _i smaller than 40 nm, in other examples ΔS _i is less than 30 nm, and in yet other examples ΔS _i is 20 nm. Smaller, and in yet other examples, ΔS _i is less than 15 nm. Such a shift in ΔS _i can be measured by plotting the wavelength to the actual reflectance of the reflector and / or alternatively, if the material and layer thickness are known, by modeling the reflector. ..

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

An omnidirectional multilayer laminate based on another embodiment disclosed herein is shown by reference number 10 in FIG. The multilayer laminate 10 has a first layer 110 and a second layer 120. It may include a voluntary reflector layer 100. Exemplary materials for the reflector layer 100, also sometimes referred to as the reflector core layer, may include Al, Ag, Pt, Cr, Cu, Zn, Au, Sn and alloys thereof. Not limited to. Thus, the reflector 100 may be a metal reflector layer, however, this is not essential. In addition, the exemplary thickness of the core reflector layer ranges from 30 nm to 200 nm.

A pair of symmetrical layers may be on the opposite side of the reflector layer 100, i.e. the reflector layer 100 has another first layer located on the opposite side of the first layer 110. Often, this causes the reflector 100 to be sandwiched between a pair of first layers. In addition, another second layer 120 may be located on the opposite side of the reflector layer 100, which results in a five-layer structure. Therefore, it should be understood that the discussion of multi-layer laminates herein further includes the possibility of mirroring for one or more core layers. Therefore, FIG. 15 may be a half view of the five-layer multilayer laminate.

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

Exemplary materials for the dry deposited nh dielectric layer 110 include, but are not limited to, CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , _SnS , TiO ₂ , ZnO, ZnS, and ZrO ₂ . In addition, the dry deposited _nh dielectric layer may have a thickness between 0.1 QW and 4.0 QW of the desired adjustment wavelength, which desired adjustment wavelength is the center wavelength of the desired reflection band. Is. The term "QW" or "thickness of QW" refers to a quarter thickness of the desired adjustment wavelength, i.e. QW = λ _cw / 4, where λ _cw is the desired adjustment wavelength. ..

The second layer 120 may be a dry sedimentary 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 preferred. It is between 2 nm and 30 nm.

FIG. 16 is a five-layer design pigment 10a having a symmetrical layer with an external protective layer 200 extending over the reflector core layer 100. The pigment 10a has a dry deposited _nh dielectric layer 110a and a dry absorber layer 120a arranged opposite to each other. The outer protective layer 200 may be a wet sedimentary protective layer and / or an _h oxide layer. The term "wet deposit" was deposited and / or formed using wet chemical techniques known to those of skill in the art, such as sol gel treatment, layer-by-layer treatment, spin coating and the like. It should be understood that it refers to layers. Typical examples of wet sedimentary layer materials include CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ , and the thickness of such layers is in the range of 5 nm to 200 nm. May be.

A list of materials that can make dry-deposited n- _dielectric layers and / or wet-deposited n _- external protective layers is shown in Table 2 below.

In one example, the external protective layer 200 may be made of two wet sedimentary layers as shown in FIG. As an example, the wet sedimentary layer 202 may be the first _nh oxide and the wet sedimentary layer 204 may be the second _nh oxide. In addition, the single external protective layer 200, layer 202, and / or layer 204 may be a mixed _nh oxide layer containing 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 below the external protective layer 200. In other words, the five-layer design pigment produced by the dry deposition method 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 external protective layer can function not only as a protective layer but also as a color enhancing layer. As an example and for illustrative purposes only, the external protective layer 200 can serve only as a protective coating and have 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, the dry deposited _nh dielectric layers 110, 110a, and the absorber layers 120, 120a. Alternatively, the external protective layer 200 increases some color effect, eg, the saturation of the pigment, with respect to the pigment 10a, and a slight shift in the "color" of the pigment to the human eye. 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 in reference number 20. The multilayer laminate 20 is similar to the multilayer laminate 10 except for an additional absorber layer 105 extending between the reflector core layer 100 and the dry deposited _hn dielectric layer 110. Further similar to the pigment 10a shown in FIG. 16, the pigment 20a is shown in FIG. 19, where symmetrical layers 105a, 110a, and 120a extend over the reflector core layer 100 and are each layer 105. , 110, 120 are arranged to face each other. The pigment 20a further has a wet deposited _hn external 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 treatment, layer-by-layer treatment, spin coating, and the like. Other known dry methods include chemical vapor deposition and physical vapor deposition, such as sputtering, electron beam deposition, and the like.

The multilayer laminates disclosed herein can be used for almost any color coating, such as pigments for paints, 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. 10-14.

To further teach the invention, but without limiting its scope by any method, examples of weather resistant omnidirectional structural color pigments and manufacturing steps for producing such pigments are discussed below. ..

<Procedure 1> Five-layer pigment coated with _two layers of ZrO Two grams of five-layer pigment was suspended in 30 ml of ethanol in a 100 ml round-bottom flask and stirred at room temperature at 500 rpm. A solution of 2.75 ml 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 with 3 ml of ethanol was added in a fixed amount. After titration, the suspension was stirred for an additional 15 minutes. The mixture is filtered, washed with ethanol followed by isopropanol and dried at 100 ° C. for 24 hours, or optionally further annealed at 200 ° C. for 24 hours to finally have the structure shown in FIG. A 5-layer pigment was obtained. If necessary, further annealing at higher temperatures may be performed.

<Procedure 2> Five-layer pigment coated with _two layers of TiO A two-gram five-layer pigment was suspended in 30 ml of IPA in a 100 ml round-bottom flask and stirred at 40 ° C. Then, a solution of 2.5 ml of titanium ethoxydo (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 with 4 ml of IPA was quantified and added. After titration, the suspension was stirred for an additional 30 minutes. The mixture is cooled to room temperature, filtered, washed with IPA, dried at 100 ° C. for 24 hours, or optionally further annealed at 200 ° C. for 24 hours to finally have the structure shown in FIG. A layer pigment was obtained. If necessary, further annealing at higher temperatures may be performed.

Table 3 below summarizes the coating, the procedure for manufacturing the coating, the thickness of the coating, the uniformity of the thickness of the coating, and the photodegradability reactivity.

From the above, Table 4 provides an inventory of the various oxide layers, substrates that can be coated, and coating thicknesses contained in this teaching.

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

In the organosilane step, any organosilane coupling agent known to those skilled in the art can be used, for example 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 illustration purposes only, and modifications, modifications, and similarities apparent to those of skill in the art are within the scope of the invention. Therefore, the scope of the present invention is defined by the claims and all equivalents thereof.

The present invention further includes the following embodiments:
1. 1. Reflective core layer,
A dry deposited high-refractive index ( _nh ) dielectric layer extending over the reflective core layer,
It has a multilayer laminate having a dry sedimentary absorber layer extending over the _nh dielectric layer and a wet _nh external oxide layer extending over the absorber layer.
A place where the multilayer laminate is smaller than 300 nm when the multilayer laminate is exposed to wide-band 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. A reflection band with a given full width at half maximum (FWHM), and a given color shift less than 30 °.
Hybrid omnidirectional structural color pigment.
2. 2. The reflective core layer is a metal core reflector layer having a thickness of 30 nm to 200 nm, and at least one of the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn and alloys thereof. The hybrid omnidirectional structural color pigment according to 1 above, which is a metal material more selected.
3. 3. The dry-deposited nh dielectric layer is a dielectric material selected from at least one of the group consisting of CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , _SnS , TiO ₂ , ZnO, ZnS, and ZrO ₂ . The hybrid omnidirectional structural color pigment according to 2 above.
4. 3. The hybrid omnidirectional structural color pigment according to 3 above, wherein the dry deposited _nh dielectric layer has a thickness of 0.1 QW to 4.0 QW for a desired adjustment wavelength.
5. 4. The absorbent material in which the dry deposition absorber layer is selected from at least one of the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si _, and Fe ₂ O3. Hybrid omnidirectional structural color pigment.
6. 5. 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. _{In 6 . _ _ _ _} The hybrid omnidirectional structural color pigment described.
8. 7. The hybrid omnidirectional structural color pigment according to 7 above, wherein the wet-deposited _nh external oxide layer has a thickness between 5 nm and 200 nm.
9. The dry-deposited n- _h dielectric layer is a pair of n- _h dielectric layers in which the reflective core layer extends between them, and the dry-deposited absorbent layer is a pair of n- _h dielectric layers between them. 8. The hybrid _{omnidirectional} according to 8. Structural color pigment.
10. 9. The hybrid omnidirectional structural color pigment according to 9 above, wherein the multilayer laminate has a thickness smaller than 2.0 μm.
11. 9. The hybrid omnidirectional structural color pigment according to 9 above, wherein the multilayer laminate has a thickness smaller than 1.5 μm.
12. 11. The hybrid omnidirectional structural color pigment according to 11 above, wherein the multilayer laminate has less than 10 layers.
13. 12. The hybrid omnidirectional structural color pigment according to 12 above, wherein the multilayer laminate has less than eight layers.
14. Bringing a reflective core layer,
Dry deposition of a high refractive index ( _nh ) dielectric layer extending over the reflector core layer,
Includes dry deposition of the absorber layer extending over the _nh dielectric layer and wet deposition of the _nh oxide layer extending over the absorber layer to produce a multilayer laminate.
Given that the multilayer stack is smaller than 300 nm when the multilayer stack is exposed to wideband 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. A reflection band with a full width at half maximum (FWHM), and a given color shift less than 30 °.
A method for manufacturing an omnidirectional structural color pigment.
15. The reflective core layer has a thickness of 30 nm to 200 nm, made of a metallic material selected from at least one of the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn and alloys thereof. Metal core reflector layer,
The dry-deposited nh dielectric layer has a thickness between 0.1 QW and 4.0 QW of the desired adjustment wavelength, and CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , _SnS , TIO ₂ , etc. 14. The method according to 14 above, which is made of a dielectric material selected from at least one of the group consisting of ZnO, ZnS, and ZrO ₂ .
16. The dry absorber layer has a thickness of 2 nm to 30 nm and is selected from at least one of the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si _, and Fe ₂ O3. The method according to 15 above, which is made from a body material.
17. The wet deposited _nh external oxide layer has a thickness of 5 nm to 200 nm and is selected from at least one of the group consisting of CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ . The method according to 16 above, which is an oxide.
18. 17. The method according to 17, wherein the multilayer laminate has less than 10 layers.
19. 17. The method according to 17, wherein the multilayer laminate has less than eight layers.
20. 17. The method according to 17, wherein the multilayer laminate has a total thickness smaller than 2.0 μm.

Claims (15)

Reflective core layer,
A dry-deposited high-refractive index dielectric layer having a refractive index equal to or greater than 2.0, which extends over the reflective core layer.
A dry deposited absorber layer extending over the high refractive index dielectric layer and a wet deposited high refractive index external oxide layer extending over the absorber layer and having a refractive index equal to or greater than 2.0. ,
Has a multi-layered laminate with
A place where the multilayer laminate is smaller than 300 nm when the multilayer laminate is exposed to wide-band 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. It has a reflection band with a given full width at half maximum (FWHM), and a given color shift less than 30 °.
The dry deposited high refractive index dielectric layer is arranged such that the dry deposited high refractive index dielectric layer exhibits an electric field of almost zero with respect to the target electromagnetic radiation wavelength.
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 of the group consisting of Al, Ag, Pt, Cr, Cu, Zn, Au, Sn and alloys thereof. It is a metallic material of choice and
The dry-deposited high-refractive index dielectric layer is a dielectric selected from at least one of the group consisting of CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , SnS, TiO ₂ , ZnO, ZnS, and ZrO ₂ . It is a material
The dry sedimentary 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 O3.
The wet-deposited high-refractive index external oxide layer is an oxide selected from at least one of the group consisting of CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ .
The hybrid omnidirectional structural color pigment according to claim 1. The hybrid omnidirectional structural color pigment according to claim 2, wherein the dry deposited high refractive index dielectric layer has a thickness of 0.1 QW to 4.0 QW for a desired adjustment wavelength. The hybrid omnidirectional structural color pigment according to claim 2, wherein the dry deposition absorber layer has a thickness of 2 nm to 30 nm. The hybrid omnidirectional structural color pigment according to claim 2, wherein the wet-deposited high-refractive index external oxide layer has a thickness of 5 nm to 200 nm. The dry-deposited high-refractive-index dielectric layer is a pair of high-refractive-index dielectric layers in which the reflective core layer extends between them, and the dry-deposited absorbent layer is a pair of the above-mentioned pair between them. A pair of dry-deposited absorber layers in which a high-refractive-index dielectric layer extends, wherein the wet-deposited high-refractive-index external oxide layer extends over the outer surface of the pair of dry-deposited absorbent layers. 5. The hybrid omnidirectional structural color pigment according to 5. The hybrid omnidirectional structural color pigment according to claim 6, wherein the multilayer laminate has a thickness smaller than 2.0 μm. The hybrid omnidirectional structural color pigment according to claim 7, wherein the multilayer laminate has a thickness smaller than 1.5 μm. The hybrid omnidirectional structural color pigment according to claim 8, wherein the multilayer laminate is less than 10 layers. The hybrid omnidirectional structural color pigment according to claim 9, wherein the multilayer laminate is less than eight layers. Bringing a reflective core layer,
Dry deposition of a high refractive index dielectric layer with a refractive index equal to or greater than 2.0 that extends over the reflective core layer.
A dry deposit of an absorber layer extending over the high refractive index dielectric layer and a high refractive index external oxide having a refractive index equal to or greater than 2.0 extending over the absorber layer. Including producing a multilayer laminate by wet depositing layers,
Given that the multilayer stack is smaller than 300 nm when the multilayer stack is exposed to wideband 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. It has a reflection band with a full width at half maximum (FWHM), and a given color shift less than 30 °.
The dry deposited high refractive index dielectric layer is arranged such that the dry deposited high refractive index dielectric layer exhibits an electric field of almost zero with respect to the target electromagnetic radiation wavelength.
A method for manufacturing an omnidirectional structural color pigment. The reflective core layer is made of a metallic 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. Have and
The dry-deposited high-refractive index dielectric layer has a thickness of 0.1QW to 4.0QW for a desired adjustment wavelength, and CeO ₂ , Nb ₂ O ₅ , SiN, SnO ₂ , SnS, TiO ₂ , ZnO, ZnS, and ZrO ₂ made from a dielectric material selected from at least one of the group.
The dry absorber layer has a thickness of 2 nm to 30 nm and is selected from at least one of the group consisting of Cr, Cu, Au, Sn, alloys thereof, amorphous Si _, and Fe ₂ O3. Made from body material,
The wet-deposited high-refractive index external oxide layer has a thickness of 5 nm to 200 nm and is at least one of the group consisting of CeO ₂ , Nb ₂ O ₅ , SnO ₂ , TiO ₂ , ZnO, and ZrO ₂ . The method according to claim 11, which is an oxide selected from the above. The method according to claim 11 or 12, wherein the multi-layer laminate has less than 10 layers. 13. The method of claim 13, wherein the multilayer laminate is less than eight layers. The method according to any one of claims 11 to 14, wherein the multilayer laminate has a total thickness smaller than 2.0 μm.

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