Basic color-changing material, preparation method and device

Abstract

The invention provides a preparation method, a material and a device of a basic color-changing material for a full-color color-changing technology. The method comprises the following steps: acquiring a spectrum of target ambient light; acquiring absorption spectrums of a plurality of groups of mixed dyes, wherein the plurality of groups of mixed dyes respectively comprise a plurality of photochromic dyes with different proportions; and comparing the absorption spectrums of the multiple groups of mixed dyes with the spectrum of the target ambient light, and selecting the mixed dye with the highest matching degree with the spectrum of the target ambient light in the absorption spectrums of the multiple groups of mixed dyes as the basic color-changing material. No matter how ambient light changes along with time, space and the like, the basic color-changing material prepared by the method can show ideal black, and when the basic color-changing material prepared by the method is applied to a full-color color-changing technology, the color gamut range of the full-color color-changing technology can be greatly widened, and the color-changing effect of the full-color color-changing technology is improved. Therefore, the technology can express colors in a richer and more complete manner.

Description

Technical Field

[0001] The present invention belongs to the technical field of photochromic materials, and in particular relates to a basic photochromic material, a preparation method and a device for full-color photochromic technology. Background Art

[0002] Color is an inherent property of an object and is usually difficult to change after it is manufactured. Existing reversible color-changing technologies, such as thermochromic materials and electrochromic materials, can only change from one color to another and cannot achieve color spectrum changes within the full color range. In addition, precise local color changes are usually not possible to produce detailed color patterns, and only global color changes can be performed on the surface of the material. In addition, there are some problems with the stability of the color-changing results. For example, thermochromic materials may not be able to stably maintain their color at room temperature and require continuous heating from a heat source to maintain the temperature, while electrochromic materials often require a continuous power supply to maintain the color state.

[0003] Compared with the above technologies, a full-color color-changing technology (Photo-Chromeleon) based on special photochromic materials can realize digital changes in the physical color of objects, allowing users to repeatedly change the color of objects through special light projection without using any traditional dyes or paints again. The basic principle of Photo-Chromeleon technology is based on a photochromic dye that is relatively stable after color change. By mixing three primary colors of cyan, magenta and yellow, and then irradiating with light projection of different wavelengths, the proportion of each primary color can be controlled and adjusted within the pixel range, thereby accurately controlling the color of the overall irradiated target. The color change principle involved in this technology utilizes the absorption spectrum characteristics of photochromic dyes. Since each photochromic dye only responds to light within a specific wavelength range, this means that the color change of the dye can depend on the wavelength of the light it irradiates. Cyan, magenta and yellow are the three primary colors in physical materials, corresponding to the complementary colors of red, green and blue light in the spectrum, respectively. The magenta dye mainly absorbs the red light spectrum, but allows green and blue light to pass through. Therefore, when red light is irradiated to a surface mixed with magenta, magenta, and yellow photochromic dyes, it will only act on the magenta dye therein to produce a color change reaction, but will not affect the magenta and yellow dyes; the magenta dye absorbs the green light spectrum, but allows red and blue light to pass through. Therefore, when green light is irradiated to a surface mixed with magenta, magenta, and yellow photochromic dyes, it will only act on the magenta dye therein to produce a color change reaction, but will not affect the magenta and yellow dyes. The yellow dye absorbs blue light, but allows red and green light to pass through. Therefore, the irradiation of blue light will cause the color of the surface containing the yellow dye to change, without affecting the magenta and magenta dyes. In Photo-Chromeleon technology, by precisely controlling the irradiation of red, green, and blue light (RGB light source), the color reaction of each dye can be adjusted separately at the microscopic level, thereby achieving precise color mixing and creation. This method utilizes the complementary color principle and color mixing theory of light. By adjusting the irradiation ratio of light of different wavelengths, the color of the surface of the object can be controlled at the pixel level, thereby generating any color change from a single color to a complex pattern, which provides flexibility for personalized design and manufacturing. In addition, due to the reversible color change characteristics of photochromic dyes, the generated colors can also be restored to their initial state by special ultraviolet light irradiation, after which the user can change the color again by light irradiation on the same object. The color change process of this technology can not only be precisely controlled, but also completely reversed, allowing the surface color of the same object to be repeatedly customized as needed.

[0004] The basic idea of ​​full-color color-changing technology (Photo-Chromeleon) is to mix photochromic dyes with different primary colors to obtain basic color-changing materials, and then the basic color-changing materials form a black base under the irradiation of the target ambient light, which is the initialization state required to create color. Black is a basic and key color in color theory, representing the deepest level of color that can be expressed by this technology. Only by producing perfect black can the color-changing effect achieve a wide range of colors from the darkest to the lightest, and ensure the integrity and richness of color expression.

[0005] The basic color-changing materials used for full-color color-changing technology prepared in the prior art have a color difference when the initial state is black under the irradiation of the target ambient light, and may even tend to other tones, resulting in the full-color color-changing technology being able to express colors only in a monotonous and limited manner. Summary of the invention

[0006] In order to solve the above-mentioned defects, the present invention proposes a basic color-changing material, a preparation method and a device.

[0007] The present invention specifically provides a method for preparing a basic color-changing material, comprising the following steps:

[0008] S1. Obtain the spectrum of target ambient light;

[0009] S2, obtaining absorption spectra of multiple groups of mixed dyes, wherein the multiple groups of mixed dyes respectively contain multiple photochromic dyes in different proportions;

[0010] S3. Compare the absorption spectra of the multiple groups of mixed dyes with the spectrum of the target ambient light, and select the mixed dye with the highest matching degree with the spectrum of the target ambient light among the absorption spectra of the multiple groups of mixed dyes as the basic color-changing material.

[0011] Further, the S2 specifically includes the following steps:

[0012] S21, mixing a plurality of the photochromic dyes in different proportions to obtain a plurality of groups of mixed dyes; S22, measuring and obtaining absorption spectra of the plurality of groups of mixed dyes obtained by mixing; or

[0013] S21, obtaining absorption spectra of a plurality of photochromic dyes; S22, calculating and obtaining absorption spectra of a plurality of groups of mixed dyes according to the absorption spectra of the plurality of photochromic dyes.

[0014] Further, S3 specifically includes the following steps:

[0015] The matching degree between the absorption spectrum of each group of the mixed dyes and the spectrum of the target ambient light is characterized by an objective function, and the mixed dye with the highest matching degree between the absorption spectrum of the multiple groups of the mixed dyes and the spectrum of the target ambient light is selected by minimizing the objective function, and the minimization method is one or more of the least squares method, gradient descent, genetic algorithm, linear programming, quadratic programming, Lagrange multiplier method, interior point method or simulated annealing particle swarm optimization algorithm.

[0016] Furthermore, the objective function is:

[0017] θ=∑ λ (I λ -∑ i x i ×A i,λ ) 2

[0018] Wherein, i=1,2,3,...; the ratios of different photochromic dyes are x1, x2, x3,..., x i ; λ is the discrete wavelength between wavelengths in the visible light range; I λ A represents the light intensity of the target ambient light at the discrete wavelength node; i,λ represents the absorptivity of the photochromic dye i at the discrete wavelength node; 0≤x i

[0019] ≤1: dye ratio x i Between 0 and 1, and x1+x2+x3+…+x i =1.

[0020] The present invention also specifically provides a basic color-changing material, which is prepared by the above-mentioned method for preparing the basic color-changing material.

[0021] Furthermore, the photochromic dye is obtained by linking a diarylethene and an ethylene glycol chain.

[0022] Furthermore, each group of the mixed dyes includes cattail, magenta, yellow, orange, green and violet photochromic dyes.

[0023] The present invention further specifically provides a device for preparing a basic color-changing material, based on the above-mentioned method for preparing the basic color-changing material, comprising:

[0024] A spectrum acquisition unit, which is used to acquire the spectrum of the target ambient light;

[0025] A mixed dye absorption spectrum acquisition unit, which acquires the absorption spectra of multiple photochromic dyes and calculates the absorption spectra of multiple groups of mixed dyes, or directly imports the absorption spectra of multiple groups of mixed dyes;

[0026] a matching unit, which receives the spectrum of the target ambient light output by the spectrum acquisition unit and the absorption spectra of the multiple groups of mixed dyes acquired by the mixed dye absorption spectrum acquisition unit, and calculates the ratio of the multiple photochromic dyes in the basic color-changing material according to the spectrum of the target ambient light and the absorption spectra of the multiple groups of mixed dyes;

[0027] a dye storage unit storing a plurality of the photochromic dyes;

[0028] The dye mixing unit mixes the multiple photochromic dyes stored in the dye storage unit according to the ratios of the multiple photochromic dyes calculated by the matching unit to obtain the basic color-changing material.

[0029] Furthermore, the spectrum acquisition unit includes a measuring module, and the measuring module is used to measure the spectrum of the target ambient light.

[0030] Further, the spectrum acquisition unit further includes a start module for starting the measurement of the measurement module;

[0031] When the preparation device is restarted, the start module starts the measurement of the measurement module, or

[0032] The starting module starts the measurement of the measuring module once at a predetermined interval.

[0033] The present invention has the following beneficial effects:

[0034] (1) The method for preparing the basic color-changing material in the present invention ensures that the absorption spectrum of the obtained basic color-changing material closely matches the spectrum of the target ambient light in the entire visible light range, so that even at a relatively low concentration, the basic color-changing material can uniformly absorb and cover the entire visible spectrum, thereby making the basic color-changing material present an appearance close to black. That is, the method for preparing the basic color-changing material in the present invention can ensure that after the obtained basic color-changing material is excited by ultraviolet light at different concentrations, its saturated hue can be close to the ideal black, and will not tend to any other hue. Regardless of how the ambient light changes with time, space, etc., the basic color-changing material prepared by this method can present an ideal black color. Applying the basic color-changing material prepared by this method to full-color color-changing technology can greatly expand the color gamut range of the full-color color-changing technology, so that the technology can express colors more richly and completely.

[0035] (2) Due to the differences in the spectrum range of illumination in different environments, such as sunlight and artificial light sources (such as fluorescent lamps), the same black dye may show a hue bias under different spectral illumination. The preparation method of the basic color-changing material disclosed in the present invention designs the ratio of the basic color-changing material based on the measured target ambient light spectrum data, so it is more targeted. This method allows the basic color-changing material to show the most ideal black color that meets the current scene under its corresponding target ambient light, without being biased towards any other hue, which greatly improves the scope of application of full-color color-changing technology in different application scenarios.

[0036] (3) The present invention significantly optimizes the color stability and repeated color change performance of the basic color-changing material by using a P-type diarylethene compound as the core compound of the basic color-changing material. Due to its excellent photochemical stability and anti-fatigue properties, the P-type diarylethene compound enables the basic color-changing material of the full-color color-changing technology to maintain its original bright color and pattern accuracy even after hundreds of light-induced color changes, and is particularly suitable for application scenarios that require long-term display or frequent color changes.

[0037] (4) The present invention significantly improves the solubility and dispersibility of the original diarylethene compound in an aqueous environment by modifying the diarylethene compound with a hydrophilic ethylene glycol chain, thereby ensuring the high uniformity of the basic color-changing material during the spraying process and the subsequent drying process; the modified basic color-changing material is both safe and environmentally friendly, and especially improves the applicability and value of full-color color-changing technology in scenarios with strict requirements on biosafety and environmental impact; the addition of the hydrophilic chain provides protection for the diarylethene core to a certain extent, reduces its direct exposure to potential degradation conditions, and thus improves the stability and service life of the molecule; by changing the length and branching structure of the ethylene glycol chain, the physicochemical properties of the overall molecule of the compound, such as solubility, viscosity and optical properties, can be further fine-tuned to optimize its performance in specific applications, further expanding the application range of the basic color-changing material in other scenarios.

[0038] (5) The preparation method of the basic color-changing material proposed in the present invention can significantly improve the color gamut range of the color-changing results compared with the prior art. On the basis of the traditional CMY primary color photochromic dyes, more photochromic dyes of other colors that can fill the gaps in the absorption spectrum of the basic color-changing materials are further introduced, and a scientific mixing and matching scheme is carried out according to the measured data. This not only enables the basic color-changing materials to achieve a more ideal black color after being excited by the color of the target ambient light, but also greatly improves the color spectrum range of the color-changing results of the full-color color-changing technology itself, so that the full-color color-changing technology can generate more accurate and richer color-changing effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0040] Figure 1 A flow chart of a method for preparing a basic color-changing material;

[0041] Figure 2 A normalized curve diagram of the target ambient light intensity distribution obtained by the spectrometer measurement;

[0042] Figure 3 It is a schematic diagram of normalized absorption intensity curves of six kinds of modified photochromic dyes in solutions at the same weight standard concentration of the present invention;

[0043] Figure 4 A conceptual schematic diagram of a process in which six photochromic dyes of different colors are mixed to form black under the excitation of target ambient light;

[0044] Figure 5 It is a comparison diagram of the absorption spectrum curve of the basic color-changing material of the control group 1 and the target ambient light intensity distribution curve;

[0045] Figure 6 The remaining light intensity distribution curve of the basic color-changing material of the control group 1 after being irradiated by the target ambient light;

[0046] Figure 7 It is a comparison diagram of the absorption spectrum curve of the basic color-changing material of the control group 2 and the target ambient light intensity distribution curve;

[0047] Figure 8 The remaining light intensity distribution curve of the basic color-changing material of the control group 2 after being irradiated by the target ambient light;

[0048] Fig. 9 It is a comparison diagram of the absorption spectrum curve of the basic color-changing material of the control group 3 of the present invention and the target ambient light intensity distribution curve;

[0049] Fig.10 The remaining light intensity distribution curve of the basic color-changing material of the control group 3 of the present invention after being irradiated by the target ambient light;

[0050] Fig.11 Comparison of the absorption spectrum curve of the basic color-changing material of experimental group 1 of the present invention and the target ambient light intensity distribution curve;

[0051] Fig.12 The remaining light intensity distribution curve of the basic color-changing material of experimental group 1 of the present invention after being irradiated by the target ambient light;

[0052] Fig.13A comparison chart of the color gamut that can be produced in the CIE-1931 color space by implementing the Photo-Chromeleon technology using the traditional CMY three primary colors (cyan, magenta, yellow) photochromic dye mixing scheme and implementing the Photo-Chromeleon technology using the multicolor primitive scheme (cyan, magenta, yellow, orange, green, purple) mixing scheme of the present invention;

[0053] Fig.14 Schematic diagram of the structure of the preparation device of the basic color-changing material. DETAILED DESCRIPTION

[0054] The technical solution of the present invention is described in detail below in conjunction with specific embodiments so that those skilled in the art can better understand and implement the technical solution of the present invention.

[0055] In order to compensate for the lack of color difference in the initial state of the basic color-changing material under the irradiation of the target ambient light, the traditional method is to continuously increase the concentration of the dye to make the human eye produce an illusory black effect, but its actual color is just another color with a very dark tone. With the increase of the dye concentration, the basic color-changing material may encounter physical and chemical limitations in application. For example, too high a concentration may involve the problem of dye solubility, which will lead to an increase in the viscosity of the solution or dye deposition and make the material unusable. The preparation method of the basic color-changing material of the present invention will be helpful in avoiding the problem of too high a concentration of a certain dye in the basic color-changing material.

[0056] In one embodiment, a method for preparing a basic color-changing material, such as Figure 1 As shown, the following steps are included:

[0057] S1. Obtain the spectrum of the target ambient light.

[0058] The specific process is as follows:

[0059] Use a spectrum analyzer to actually measure the light intensity distribution of the target ambient light implementing the color change technology in the visible light band from 400nm to 700nm, and perform normalization:

[0060]

[0061] Among them, I is the original light intensity data, I min is the minimum value in the light intensity data, I max is the maximum value in the light intensity data. In this way, all light intensity data will be converted to values ​​between 0 and 1, see Figure 2 .

[0062] S2, obtaining absorption spectra of multiple groups of mixed dyes, wherein the multiple groups of mixed dyes respectively contain multiple photochromic dyes in different proportions. S2 specifically comprises the following steps:

[0063] S21, obtaining absorption spectra of a plurality of photochromic dyes; S22, calculating and obtaining absorption spectra of a plurality of groups of mixed dyes according to the absorption spectra of the plurality of photochromic dyes.

[0064] Among them, S21, obtaining the absorption spectra of multiple photochromic dyes, that is, detecting the visible light spectrum absorbance of different basic photochromic dyes to obtain the absorption spectrum of each basic photochromic dye, the specific process is as follows:

[0065] Prepare standard concentration solutions of uniform weight of various photochromic dyes and test the absorbance of each solution between 400nm and 700nm of the visible light spectrum. The concentration of the dye should be sufficient to make the absorbance measurement within the effective range of the instrument while avoiding possible deviations at high concentrations (such as nonlinear absorbance changes caused by solute interactions). Then use a spectrophotometer to test the absorption spectrum of each solution. For the absorption data of the dye, the data of the spectrophotometer is already in the range of 0 to 1, see Figure 3 , no further normalization is required. However, if the original data is not based on a 0 to 1 scale or to unify the data processing pipeline, the same normalization formula can be used:

[0066]

[0067] Here, A is the raw absorbance data, A min is the minimum value of absorption rate, A max The maximum value of the absorption rate.

[0068] Furthermore, the absorption spectra of multiple groups of mixed dyes can be calculated based on the absorption spectrum of a single photochromic dye and the mixing schemes of multiple photochromic dyes in different proportions, such as by using a weighted average method, a linear superposition method or a spectrum fitting method.

[0069] S3. Compare the absorption spectra of the multiple groups of mixed dyes with the spectrum of the target ambient light, and select the mixed dye with the highest matching degree with the spectrum of the target ambient light among the absorption spectra of the multiple groups of mixed dyes as the basic color-changing material.

[0070] The specific process is as follows:

[0071] The optimal ratio of each dye in the plurality of groups of mixed dyes is found by using an optimization method, so that the absorption spectrum of the mixed dye group matches the spectrum of the detected target ambient light to the highest degree. The matching degree between the absorption spectrum of the mixed dyes of different groups and the spectrum of the ambient light is characterized by an objective function. Assume that the dye ratios of different dyes are x1, x2, x3, ..., x i , then the objective function can be a similarity measure between absorption spectra, such as mean square error, mean absolute error, root mean square error, relative error, maximum absolute error, Pearson correlation coefficient, cosine similarity, Kullback-Leibler divergence (information divergence) and other measurement methods. In this embodiment, the mean square error is used as a method to characterize the similarity measure:

[0072] θ=∑ λ (I λ -Σ i x i ×A i,λ ) 2

[0073] Wherein, i = 1, 2, 3, ...; λ is a discrete wavelength between 400nm and 700nm of visible light. For example, the calculation is performed at intervals of 10nm, and the discrete calculated wavelengths are 400nm, 410nm, 420nm, 430nm, ..., 700nm. This can reduce the calculation complexity while maintaining sufficient accuracy. λ Represents the light intensity of the target ambient light at discrete wavelength nodes; A i,λ represents the absorbance of dye i at discrete wavelength nodes; 0≤x i ≤1: The dye ratio must be between 0 and 1; x1+x2+x3+…+x i =1: The sum of the dye ratios must be equal to 1.

[0074] Finally, mathematical optimization methods can be used to minimize the objective function. In addition to traditional mathematical optimization methods (such as least squares method, gradient descent, genetic algorithm, linear programming, etc.), heuristic algorithms (such as simulated annealing, particle swarm optimization, etc.) can also be introduced. Through iterative calculation, a set of optimal dye ratios x1:x2:x3:…:x i This ratio can be understood as a weight ratio or converted into a concentration ratio. The absorption spectrum of the base material obtained by mixing in this ratio can theoretically best match the spectrum of the current lighting conditions, and can produce a relatively ideal black at low or high concentrations without being biased towards other colors in the color spectrum.

[0075] In the optimization process, the heuristic algorithm and the gradient descent method are combined. In the early stage, the heuristic algorithm is used for global search, and in the later stage, the gradient descent method is used for local fine optimization, which can greatly improve the overall optimization efficiency and effect.

[0076] Specific optimization methods used to minimize the objective function include, but are not limited to, least squares method, gradient descent, genetic algorithm, linear programming, quadratic programming, Lagrange multiplier method, interior point method, simulated annealing, and particle swarm optimization.

[0077] The preparation method of the basic color-changing material in this embodiment ensures that the absorption spectrum of the prepared basic color-changing material closely matches the spectrum of the target ambient light in the entire visible light range, so that even at a lower concentration, the basic color-changing material can uniformly absorb and cover the entire visible spectrum, thereby making the basic color-changing material show an appearance close to black. That is, the preparation method of the basic color-changing material in this embodiment can ensure that the saturated hue of the prepared basic color-changing material can be close to the ideal black after being excited by ultraviolet light at different concentrations, and will not tend to any other hue, which can make the full-color color-changing technology more complete and enrich the expression of color needs, and can avoid the problem of excessive concentration of a certain dye in the basic color-changing material.

[0078] In addition, due to the differences in the range of illumination spectrum in different environments, such as sunlight and artificial light sources (such as fluorescent lamps), the same black dye may show a hue bias under different spectral illumination. Therefore, it is also very important to specially design the basic color-changing material according to the lighting conditions of different target ambient light and technical application scenarios to achieve accurate black expression. The preparation method of the basic color-changing material disclosed in this embodiment designs the ratio of the basic color-changing material based on the measured target ambient light spectrum data, so it is more targeted. This method allows the basic color-changing material to present the most ideal black that meets the current scene under its corresponding target ambient light, without being biased towards any other hue, which greatly improves the scope of application of full-color color-changing technology in different application scenarios.

[0079] In other embodiments, S2 may further specifically include the following steps: S21, mixing the plurality of photochromic dyes in different proportions to obtain a plurality of groups of mixed dyes; S22, measuring and acquiring the absorption spectra of the plurality of groups of mixed dyes obtained by mixing, and the measuring tool may be a spectrophotometer or the like.

[0080] In order to investigate the actual effect of the preparation method of the basic color-changing material in the above embodiment, the following comparative experiment was conducted. The comparative experiment includes four experimental groups, namely control group 1, control group 2, control group 3 and experimental group 1.

[0081] Control group 1

[0082] A basic color-changing material comprises the following weight parts of photochromic dyes: 1 part of Cyan dye, 1 part of Magenta dye, and 1 part of Yellow dye, wherein the photochromic dye is prepared by the method of the present invention.

[0083] In the process of mixing photochromic dyes, only the original three primary colors, namely, cyan, magenta, and yellow, are considered, and the dyes are simply mixed in a weight ratio of 1:1:1. The comparison diagram of the obtained spectral absorption curve and the intensity distribution of the target ambient light (natural light) is shown in the attached manual. Figure 5 At this time, after being absorbed by the basic color-changing material, the remaining target ambient light will be reflected because it is not absorbed. The spectral distribution curve is shown in the attached manual. Figure 6 As shown, it can be seen that there is an obvious light intensity distribution in the blue light band, green light band, and part of the red light band of the spectrum, especially in the blue light band and the green light band where the light intensity is higher. At this time, the black tone will be obviously bluish-green.

[0084] Control group 2

[0085] A basic color-changing material comprises the following photochromic dyes in parts by weight: 1 part of Cyan dye, 1 part of Magenta dye, 1 part of Yellow dye, 1 part of Orange dye, 1 part of Violet dye, and 1 part of Green dye. The photochromic dye is prepared by the method of the present invention.

[0086] If Cyan, Magenta, Yellow, Orange, Green, and Violet are simply mixed in a weight ratio of 1:1:1:1:1:1, the absorption curves of the corresponding basic color-changing materials and the intensity distribution of the target ambient light (natural light) are compared as shown in the figure below. Figure 7 As shown, after being absorbed by the basic color-changing material, the spectral distribution curve of the remaining reflected target ambient light is as follows Figure 8 As shown in the figure, the addition of orange, purple and green photochromic dyes effectively fills the gaps in the absorption spectrum, so that the overall mixed dye can absorb the target ambient light in the visible light wavelength range more evenly and completely. However, although this ratio of mixed dyes shows almost perfect absorption efficiency in the red light region and minimizes the reflection of red light, in the green and blue light regions, a part of the target ambient light is still not absorbed and is reflected. Therefore, the color perceived by the human eye when observing the dye at this time is still not perfect black, and its color has a certain degree of blue and green tones.

[0087] Control group 3

[0088] A basic color-changing material comprises three photochromic dyes, namely cyan, magenta and yellow, wherein the photochromic dyes are prepared by the method of the present invention.

[0089] According to the preparation method of the basic color-changing material disclosed above, the optimal weight ratio of cyan, magenta and yellow dyes can be obtained to be 0.85:1.37:2.95. At this time, the absorption curve of the basic color-changing material obtained by mixing according to this ratio after being saturated by ultraviolet light excitation and the intensity distribution of the target ambient light (natural light) are compared as shown in the figure below: Fig. 9 As shown, after being absorbed by the basic color-changing material, the spectral distribution curve of the remaining reflected target ambient light is as follows Fig.10 As shown. It can be seen that the blue light reflected by the basic color-changing material has been significantly reduced, but it still exists. However, the intensity of the reflected light in the yellow light band and part of the red light band is more obvious. The color of the overall dye is not an ideal black, but tends to be dark gray, with a certain yellow or red hue.

[0090] Experimental Group 1

[0091] A basic color-changing material comprises six photochromic dyes, namely, cyan, magenta, yellow, orange, violet and green, wherein the photochromic dyes are prepared by the method of the present invention.

[0092] According to the preparation method of the basic color-changing material disclosed above, the optimal weight ratio of Cyan, Magenta, Yellow, Orange, Green and Violet is 0.90:1.71:2.91:2.00:1.29:1.02. The comparison diagram of the absorption curve of the basic color-changing material obtained by mixing according to the ratio after being excited and saturated by the target ambient light and the intensity distribution of the target ambient light is shown in the attached figure of the specification. Fig.11 As shown in the figure, after being absorbed by the basic color-changing material, the spectral distribution curve of the remaining reflected target ambient light is as shown in the attached manual. Fig.12As shown. It can be seen that after the optimization is completed, the overall dye has almost achieved perfect absorption rate in the visible light range, and the light of all bands is almost completely absorbed without leakage. Only in the part of the blue light band less than about 450nm and the part of the red light band greater than 670nm, there is a weak light intensity. However, since the human eye is almost insensitive to the light in these two areas, the dyes mixed in the optimal ratio create a nearly ideal black in the visual sense, without biased towards any other hue.

[0093] Fig.13 The dotted line shows the color gamut that can be achieved using the Photo-Chromeleon technology using traditional Cyan, Magenta, and Yellow photochromic dyes. Fig.13 The solid line portion shows the color gamut range that can be achieved by implementing the Photo-Chromeleon technology by using photochromic dyes of multiple primitive colors, namely, Cyan, Magenta, Yellow, Orange, Green, and Violet, and mixing them in an optimal ratio. It can be clearly seen that the dyes configured by the method of the present invention have a significantly wider color gamut and can obviously present richer colors.

[0094] In one embodiment, a basic color-changing material is prepared according to the preparation method of the basic color-changing material in the above embodiment. No matter how the ambient light changes with time, space, etc., the basic color-changing material prepared by this method can present an ideal black color. The basic color-changing material prepared by this method is applied to full-color color-changing technology, which can greatly expand the color gamut range of the full-color color-changing technology, so that the technology can express colors more richly and completely.

[0095] For example, six different photochromic dyes of magenta, yellow, orange, green and purple are mixed according to the preparation method of the basic color-changing material in the above embodiment to obtain a basic color-changing material, and then excited by the target ambient light (ultraviolet light source) to form black, such as Figure 4 shown.

[0096] In one embodiment, the photochromic dye used to make the basic color-changing material is obtained by linking a diarylethene with an ethylene glycol chain.

[0097] The specific process is as follows:

[0098] In this embodiment, diarylethene is selected as the basic compound, and the basic compound is modified and characterized by introducing an ethylene glycol chain into the diarylethene molecule to obtain the photochromic dye.

[0099] Specifically, the diarylethene may be a P-type diarylethene compound, and the ethylene glycol chain is hydrophilic.

[0100] There are many types of photochromic materials, and different systems have different properties. In order to implement this technology, it is necessary to focus on factors such as the stability, fatigue resistance and applicability of the photochromic materials used. Specifically, first, the implementation of this technology requires that the color of the material is stable and lasting under natural conditions after the color change is completed; second, after multiple light cycles, the compound can still maintain the ability to respond to light, and has excellent fatigue resistance to repeat the color change; in addition, this technology also requires the color-changing material itself to have good dispersibility and functionality in other media, so that it can be suitable for different application scenarios. Spiropyran compounds have the problems of insufficient fatigue resistance and short life at room temperature, and cannot undergo multiple color change cycles. Although naphthothiophene compounds and azobenzene compounds can change color, their color change persistence is poor. After the ultraviolet light stops irradiation, the color usually quickly returns to the initial state within a few seconds. Not all photochromic materials can achieve good and uniform dispersion in other media. The lack of this characteristic may hinder the effective mixing of photochromic dyes with other materials and the implementation and application of this technology.

[0101] Currently available photochromic substances are mainly divided into P-type photochromic dyes (Photochromic type) and T-type photochromic dyes (Thermally reversible type). P-type photochromic dyes refer to those whose color change effect can only be stimulated under light of a specific wavelength (usually ultraviolet light), and the color restoration can only occur under light irradiation of another wavelength. Therefore, they are more stable after color change and are not affected by other environmental factors. T-type photochromic dyes will also change color under light of a specific wavelength (usually ultraviolet light), but unlike P-type, they can return to their original color state only by heat energy. Since T-type photochromic dyes are easily affected at room temperature, they generally disappear quickly after being irradiated with ultraviolet light. In order to make the color change effect caused by light irradiation last stably, and to avoid other environmental stimuli such as heat source, humidity and other factors from having an adverse effect on the color change result, this embodiment uses P-type stable photochromic materials as the preferred materials for implementing this technology in the selection of photochromic materials. The specific P-type stable photochromic compounds include diarylethene compounds and fulgides compounds. In terms of photochromic stability and fatigue resistance of repeated color changes, diarylethene compounds usually show better performance. Therefore, this embodiment selects diarylethene compounds as the basic compounds for realizing this technology, and particularly emphasizes the selection of dyes with good stability, good fatigue resistance and good color depth as the basic compound substrate in diarylethene. The color change characteristics of these materials are that the initial state should be colorless and transparent, and they will gradually change into corresponding colors when receiving ultraviolet light irradiation in a special band.

[0102] Among them, the specific structure of the components of the photochromic dye can be referred to as follows:

[0103]

[0104] Secondly, in order to implement this technology, this embodiment adopts a strategy of further characterizing the diarylethene basic compound. Specifically, the material used in this embodiment is to link diarylethene with a hydrophilic ethylene glycol chain, and the beneficial effects include: First, this structural design significantly increases the hydrophilicity of the diarylethene dye molecule, ensuring that the molecule can be more effectively dissolved in an aqueous environment, which is extremely critical for the application of basic color-changing materials. One of the important means of implementing full-color color-changing technology is to dissolve the basic color-changing material in a liquid environment and spray it on the surface of other objects. Only when the basic color-changing material has good hydrophilicity can the color molecules be evenly dispersed in the solution to ensure that the basic color-changing material after spraying can be evenly attached to the surface of the object, preventing the basic color-changing material from crystallizing or agglomerating after the liquid dries, resulting in uneven coverage; Second Second, the introduced ethylene glycol chain has good biocompatibility and low toxicity, making the basic color-changing material both safe and environmentally friendly, which improves the applicability and value of full-color color-changing technology in scenarios with strict requirements on biosafety and environmental impact; third, the addition of hydrophilic chains provides protection for the diarylethene core to a certain extent, reducing its direct exposure to potential degradation conditions, thereby improving the stability and service life of the molecule; fourth, by changing the length and branching structure of the ethylene glycol chain, the physicochemical properties of the overall molecule, such as solubility, viscosity and optical properties, can be finely controlled again to optimize its performance in specific applications, further expanding the application range of basic color-changing materials in other scenarios.

[0105] Among them, the structure of the diarylethene compound obtained by modifying the diarylethene compound with polyethylene glycol can be referred to as follows:

[0106]

[0107] In one embodiment, a basic color-changing material, each group of the mixed dyes selected includes more than just cattleya, magenta and yellow photochromic dyes.

[0108] Specifically, it means that on the basis of the traditional three primary photochromic dyes of cyan, magenta and yellow, more photochromic dyes that can fill the gaps in the absorption spectrum of the mixture are further introduced, such as orange, green and violet photochromic dyes, so that the mixture can achieve a more ideal black, while greatly expanding the color gamut of the color change effect.

[0109] The formation of dye color is based on its absorption of light of specific wavelengths in ambient light, and reflection or transmission of light of other wavelengths to the human eye, and different stimulations to the cone cells of the human eye, so that the human eye can perceive color. If the dye can completely absorb all the light of all bands in the ambient light, the effect fed back to the human eye is perfect black. At present, the prior art advocates the approximate formation of black by mixing photochromic dyes of cattleya, magenta and yellow. However, the absorption spectra of the dyes of these three primary colors have their own specific ranges, and after mixing, they still cannot continuously and completely cover the spectrum range of the entire visible light, so it is impossible to create an ideal black. At the same time, although in color theory, the traditional CMY (cattleya, magenta, yellow) color model can simulate other wide colors by mixing these three primary colors of different depths, there are still some colors that are difficult to accurately copy or express, especially some bright or specific tones, which limits the color spectrum limit of the color change effect that the technology can achieve.

[0110] The preparation method of the basic color-changing material proposed in this embodiment can significantly improve the color gamut range of the color-changing results compared with the prior art. On the basis of the traditional CMY primary color photochromic dyes, more photochromic dyes of other colors that can fill the gaps in the absorption spectrum of the basic color-changing materials are further introduced, and a scientific mixing and matching scheme is carried out according to the measured data, which can not only make the basic color-changing materials reach a more ideal black after being excited by the color of the target ambient light, but also greatly improve the color spectrum range of the color-changing results of the full-color color-changing technology itself, so that the full-color color-changing technology can generate more accurate and richer color-changing effects.

[0111] In one embodiment, the basic color-changing material can be applied to the target object. The specific method can be to dissolve the basic color-changing material in a liquid material with good adhesion, and then evenly spray it on the surface of the target object to form a uniform color-changing film. Since the diarylethene basic color-changing material modified by the ethylene glycol chain has good solubility, the mixed dye can generally be fully dissolved in a variety of finished liquid materials such as paints, printing inks, and certain cosmetics, so that its pigment molecules can be evenly dispersed in the liquid and form a uniform film during the curing or drying process. Since the initial state of the basic color-changing material is usually colorless and transparent, it will not affect the original color and appearance of the object when sprayed on the surface of any object. It will only start to change color under the irradiation of the target ambient light, and gradually tend to a saturated state, and finally form a perfect black.

[0112] In other embodiments, in addition to the method of dissolving the basic color-changing material in liquid and spraying it on the surface of an object, the basic color-changing material can also be mixed into solid materials, or applied to fabrics and fiber materials. Each application method will involve a different attachment and fixing process of the basic color-changing material.

[0113] In one embodiment, Fig.14 As shown, a basic color-changing material preparation device 100, based on the above-mentioned basic color-changing material preparation method, includes a matching unit 110, a spectrum acquisition unit 120, a mixed dye absorption spectrum acquisition unit 130, a dye storage unit 140 and a dye mixing unit 150.

[0114] The spectrum acquisition unit 120 is used to acquire the spectrum of the target ambient light, and the acquisition method may include measurement or importing, etc. The mixed dye absorption spectrum acquisition unit 130 is used to acquire the absorption spectra of multiple groups of mixed dyes, and specifically, it can directly import the absorption spectra of multiple groups of mixed dyes; or acquire the absorption spectra of multiple photochromic dyes, and calculate the absorption spectra of multiple groups of mixed dyes through the absorption spectra of multiple photochromic dyes. The absorption spectra of multiple photochromic dyes can be obtained by directly measuring the absorption spectra of multiple photochromic dyes stored in the dye storage unit, or by importing data.

[0115] The matching unit receives the spectrum of the target ambient light output by the spectrum acquisition unit and the absorption spectra of multiple groups of mixed dyes acquired by the mixed dye absorption spectrum acquisition unit, and calculates the proportion of the multiple photochromic dyes in the basic color-changing material according to the spectrum of the target ambient light and the absorption spectra of multiple groups of mixed dyes.

[0116] The dye storage unit stores a plurality of photochromic dyes. The dye mixing unit mixes the plurality of photochromic dyes stored in the dye storage unit according to the ratios of the plurality of photochromic dyes calculated by the matching unit to obtain a basic color-changing material.

[0117] The preparation device of the basic color-changing material in this embodiment can prepare different basic color-changing materials according to different target ambient lights, so that the basic color-changing material can present the most ideal black color that matches the current scene under its corresponding target ambient light, without being biased towards any other tones, and is suitable for different application scenarios.

[0118] In one embodiment, a device for preparing a basic color-changing material may further include an output unit, and the output unit is used for the basic color-changing material obtained by the dye mixing unit.

[0119] In one embodiment, the spectrum acquisition unit may include a measurement module, and the measurement module is used to measure the spectrum of the target ambient light. The measurement module may be a spectrum analyzer, etc.

[0120] In one embodiment, the spectrum acquisition unit further includes a start-up module for starting the measurement of the measurement module. When the preparation device of the basic color-changing material is restarted, the start-up module starts the measurement of the measurement module. Specifically, each time the user turns on the preparation device of the basic color-changing material, the start-up module issues a measurement instruction to the measurement module, driving the measurement module to re-measure the spectrum of the target ambient light. Thus, each time the user prepares the basic color-changing material, the basic color-changing material prepared can be closer to the ideal black under the stimulation of the target ambient light at the current moment, so that the subsequent color expression is richer and more complete.

[0121] In one embodiment, the start module starts the measurement of the measurement module once every predetermined time interval, so that the measurement module can periodically measure the spectrum of the target ambient light, timely update the ratio of multiple photochromic dyes in the basic color-changing material, and ensure that the basic color-changing material output by the output unit each time can better meet the needs, thereby facilitating the subsequent color expression to be richer and more complete. Among them, the predetermined time can be set according to the change speed of the target ambient light. For example, if the target ambient light changes faster, the predetermined time can be set shorter, and if the target ambient light changes slower, the predetermined time can be set longer.

[0122] In one embodiment, the start module can also be manually operated so that the start module starts the measurement of the measurement module, and manual control is more flexible and reliable.

[0123] In one embodiment, the spectrum acquisition unit may further include a data processing module, and the data processing module is used to normalize the light intensity distribution measured by the measurement module and obtain the spectrum of the target ambient light.

[0124] In one embodiment, an electronic device includes: at least one processor and at least one memory, wherein the memory stores computer-readable instructions; the computer-readable instructions are executed by one or more of the processors, so that the electronic device implements the method for preparing the basic color-changing material as described above.

[0125] In one embodiment, a storage medium stores computer-readable instructions thereon, wherein the computer-readable instructions are executed by one or more processors to implement the above-mentioned method for preparing the basic color-changing material.

[0126] The above embodiments are only used to illustrate the present invention, and the protection scope of the present invention is not limited to the above embodiments. A person skilled in the art can achieve the purpose of the present invention according to the contents disclosed in the present invention, and any improvement and deformation made based on the concept of the present invention shall fall within the protection scope of the present invention, and the specific protection scope shall be subject to the claims.

Claims

1. A method for preparing a basic color-changing material, It is characterized in that The following steps are involved: S1. Obtain the spectrum of target ambient light; S2, obtaining absorption spectra of multiple groups of mixed dyes, wherein the multiple groups of mixed dyes respectively contain multiple photochromic dyes in different proportions; S3. Compare the absorption spectra of the multiple groups of mixed dyes with the spectrum of the target ambient light, and select the mixed dye with the highest matching degree with the spectrum of the target ambient light among the absorption spectra of the multiple groups of mixed dyes as the basic color-changing material.

2. The method for preparing the basic color-changing material according to claim 1, It is characterized in that The S2 specifically includes the following steps: S21, mixing a plurality of the photochromic dyes in different proportions to obtain a plurality of groups of mixed dyes; S22, measuring and obtaining absorption spectra of the plurality of groups of mixed dyes obtained by mixing; or S21, obtaining absorption spectra of a plurality of photochromic dyes; S22, calculating and obtaining absorption spectra of a plurality of groups of mixed dyes according to the absorption spectra of the plurality of photochromic dyes.

3. The method for preparing the basic color-changing material according to claim 1 or 2, It is characterized in that S3 specifically includes the following steps: The matching degree between the absorption spectrum of each group of the mixed dyes and the spectrum of the target ambient light is characterized by an objective function, and the mixed dye with the highest matching degree between the absorption spectrum of the multiple groups of the mixed dyes and the spectrum of the target ambient light is selected by minimizing the objective function, and the minimization method is one or more of the least squares method, gradient descent, genetic algorithm, linear programming, quadratic programming, Lagrange multiplier method, interior point method or simulated annealing particle swarm optimization algorithm.

4. The method for preparing the basic color-changing material according to claim 3, It is characterized in that The objective function is: θ=∑ λ (I λ -∑ i x i ×A i,λ ) 2 Wherein, i=1, 2, 3, ...; the ratio of different photochromic dyes is x 1 , x 2 , x 3 ,…,x i ; λ is the discrete wavelength between wavelengths in the visible light range; I λ A represents the light intensity of the target ambient light at the discrete wavelength node; i,λ represents the absorptivity of the photochromic dye i at the discrete wavelength node; 0≤x i ≤1: dye ratio x i is between 0 and 1, and x 1 +x 2 +x 3 +…+x i =1.

5. A basic color-changing material, It is characterized in that It is prepared by the preparation method of the basic color-changing material as described in any one of claims 1 to 4.

6. The basic color-changing material according to claim 5, It is characterized in that The photochromic dye is obtained by linking a diarylethene and an ethylene glycol chain.

7. The basic color-changing material according to claim 5, It is characterized in that Each group of mixed dyes includes cattleya, magenta, yellow, orange, green and violet photochromic dyes.

8. A device for preparing a basic color-changing material, based on the method for preparing a basic color-changing material according to any one of claims 1 to 4, It is characterized in that include: A spectrum acquisition unit, which is used to acquire the spectrum of the target ambient light; A mixed dye absorption spectrum acquisition unit, which acquires the absorption spectra of multiple photochromic dyes and calculates the absorption spectra of multiple groups of mixed dyes, or directly imports the absorption spectra of multiple groups of mixed dyes; a matching unit, which receives the spectrum of the target ambient light output by the spectrum acquisition unit and the absorption spectra of the multiple groups of mixed dyes acquired by the mixed dye absorption spectrum acquisition unit, and calculates the ratio of the multiple photochromic dyes in the basic color-changing material according to the spectrum of the target ambient light and the absorption spectra of the multiple groups of mixed dyes; a dye storage unit storing a plurality of the photochromic dyes; The dye mixing unit mixes the multiple photochromic dyes stored in the dye storage unit according to the ratios of the multiple photochromic dyes calculated by the matching unit to obtain the basic color-changing material.

9. The device for preparing the basic color-changing material according to claim 8, It is characterized in that The spectrum acquisition unit includes a measuring module, and the measuring module is used to measure the spectrum of the target ambient light.

10. The device for preparing the basic color-changing material according to claim 9, It is characterized in that The spectrum acquisition unit further comprises a start module for starting the measurement of the measurement module; When the preparation device is restarted, the start module starts the measurement of the measurement module, or The starting module starts the measurement of the measuring module once at a predetermined interval.

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