Oily structural color pigment ink and application thereof

Abstract

The invention discloses oily structural color pigment ink and application thereof, and belongs to the technical field of preparation of photonic crystal materials. The oily structural color pigment ink comprises the following components: at least one block polymer brush, at least one resin or at least one resin precursor and at least one organic solvent. The oily structural color pigment ink provided by the invention is a layered structural color material obtained by self-assembly based on a block polymer brush microphase separation principle. The provided oily structural color pigment ink can be compatible with most of common pigment coloring methods, including but not limited to silk-screen printing, spraying, ink-jet printing and intaglio printing. The structural color of the oil-based structural color pigment ink is not limited to a visible light wave band and covers an ultraviolet spectrum, a visible spectrum and an infrared spectrum, and the wavelength range of the covered electromagnetic spectrum is 200-2000 nm.

Description

Technical Field

[0001] The invention belongs to the technical field of photonic crystal material preparation, and in particular relates to an oily structural color pigment ink and application thereof. Background Art

[0002] Pigments are substances used for coloring, which can be evenly dispersed in various media, such as oils, resins, water, organic solvents, etc., to provide color and hiding power. They are widely used in industries such as coatings, inks, plastics, rubber, ceramics, papermaking, textile printing and dyeing, and cosmetics. Historically, the pigment industry has always played an important role, providing rich and colorful colors for artistic creation, industrial manufacturing, and daily life. However, as time goes by, the development of this industry has gradually exposed some problems and limitations. First, the production process of traditional pigments is often accompanied by high energy consumption and high pollution. The production of many pigments requires the use of toxic or harmful chemicals, which may pose a threat to the environment and human health during the production process. In addition, the extraction and processing of pigments may also lead to waste of resources and ecological damage. Secondly, the performance of traditional pigments has limitations in certain application areas. For example, they may perform poorly in terms of light resistance, heat resistance, chemical corrosion resistance, etc., and the dyes or pigments themselves will slowly decompose and fade over time, which limits their use in high-end applications. Furthermore, the sustainability of traditional pigments is becoming increasingly prominent. With the global emphasis on environmental protection and sustainable development, the production and use of traditional pigments have been increasingly restricted. This requires the pigment industry to find new materials and technologies to reduce the impact on the environment.

[0003] Structural color is an optical phenomenon produced by photonic crystals (PhCs). This artificial microstructure material has important application value in the field of optics, especially in the generation and regulation of color. Photonic crystals can modulate light waves through their periodic structure to produce non-pigmentary colors. These colors are produced by optical effects such as scattering, interference and diffraction of light by the microstructure on the surface of the material. There are many examples of structural colors in nature, which show colors in unique ways in organisms. For example, butterfly wings, peacock feathers, beetle shells, etc. The colors of these organisms often come from the selective reflection of specific wavelengths by their special periodic nanostructures. The wings of the blue morpho butterfly are typical one-dimensional photonic crystals, whose structure can produce bright blue structural colors. The feathers of peacocks show the effect of two-dimensional photonic crystals, and their microscopic periodic stripe structure can reflect bright structural colors. In addition, the gem Opal is famous for its internal accumulation of SiO 2The small balls show a special color change effect and are known as the palette of gemstones. Even in daily life, the cross section of braised beef may show the effect of structural color. The arrangement of its muscle fibers forms a two-dimensional photonic crystal structure, reflecting a specific luster.

[0004] At present, the preparation of structural color materials mainly adopts the following methods: (1) Electron beam lithography: The two-dimensional photonic crystal film is prepared on the substrate by electron beam direct writing and reactive ion beam etching. This method has high precision, but the processing time is long and the cost is high; (2) Colloidal particle self-assembly technology: The three-dimensional photonic crystal is formed by the self-assembly of colloidal microspheres in solution. This method takes a long time to prepare and is sensitive to external perturbations, which may lead to structural defects. (3) Nanoimprint technology: The photonic crystal structure is quickly replicated by imprinting. It is suitable for large-area preparation, but there may be challenges in controlling the imprint depth and uniformity. (4) Femtosecond laser direct writing: The photonic crystal structure is directly written on the material surface using a femtosecond laser. High-precision three-dimensional structure can be obtained, but the equipment cost is high and the production efficiency is relatively low. (5) Chemical vapor deposition: The photonic crystal is grown by chemical vapor deposition technology, and high-quality three-dimensional photonic crystals can be obtained, but the preparation process is complicated and has high requirements for equipment and environment. (6) Sol-gel method: The cost of preparing photonic crystals by sol-gel method is low, but it is difficult to accurately control the aperture and shape, which may affect the performance of photonic crystals. (7) Multi-beam coherent holography technology: Rapid preparation of photonic crystals is achieved through multi-beam interference, which is suitable for a variety of lattice types, but it is difficult to prepare a complete photonic band gap in the visible light region due to the limitation of laser wavelength. Summary of the invention

[0005] The object of the present invention is to provide an oily structural color pigment ink and its application. The oily structural color pigment ink provided by the present invention is a layered structural color material obtained by self-assembly based on the microphase separation principle of block polymer brushes. The provided oily structural color pigment ink is compatible with most common pigment coloring methods, including but not limited to screen printing, spraying, inkjet printing, and gravure printing. The structural color of the oily structural color pigment ink is not limited to the visible light band, but covers the ultraviolet spectrum, visible spectrum, and infrared spectrum, and the wavelength range of the electromagnetic spectrum covered is 200nm-2000nm.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] One of the technical solutions of the present invention is to provide an oil-based structural color pigment ink, the components of which include: at least one block polymer brush (BBCP), at least one resin or at least one resin precursor and at least one organic solvent;

[0008] The blocks in the block polymer brush can undergo microphase separation to form a lamellar domain;

[0009] The resin or a resin generated from a precursor of the resin is compatible with at least one block of the block polymer brush and has a light transmittance of not less than 50%.

[0010] The block polymer brush used in the present invention can undergo microphase separation by self-assembly, heating to a specific temperature, solvent volatilization-induced assembly, or printing processes such as scraping and the like.

[0011] The block polymer brush (bottle brush-like block polymer) in the present invention refers to a polymer material with a special structure, which is characterized by densely grafting side chain polymers on the polymer main chain to form a brush-like morphology. The design and synthesis of this structure usually rely on precise polymerization techniques, such as living free radical polymerization, atom transfer radical polymerization (ATRP) and reversible addition fragmentation chain transfer polymerization (RAFT), which also bring special physical and chemical properties to the block polymer brush. In particular, the densely grafted side chains make the self-assembly behavior of the block polymer brush very different from that of general block polymers, making it easier to form ordered nanostructures such as photonic crystals and nanowires through self-assembly. These structures have potential applications in the fields of optics and electronics. By changing the composition and degree of polymerization of the block polymer brush, its self-assembly behavior can be regulated to prepare nanostructures with specific morphology and chemical composition.

[0012] Preferably, the block polymer brush comprises: poly (polystyrene)-b-poly (polyethylene glycol) (PPS-b-PPEO), poly (tert-butyl acrylate)-b-poly (polyethylene glycol) (PPtBA-b-PPEO), poly (polydimethylsiloxane)-b-poly (polyethylene glycol) (PPDMS-b-PPEO), poly (methyl methacrylate)-b-poly (polyethylene glycol) (PPMMA-b-PPEO), poly (methyl acrylate)-b-poly (polyethylene glycol) (PPMA-b-PPEO), poly (polyacrylonitrile)-b-poly (polyethylene glycol) (PPAN-b-PPEO), poly (lactic acid)-b-poly (polyethylene glycol) (PPLA-b-PPEO), poly (ε-caprolactone)-b-poly (polyethylene glycol) (PPCL-b-PPEO), poly (polyethylene)-b-poly (polyethylene glycol) (PPE-b-PPEO), poly (polypropylene)-b-poly (polyethylene glycol) (PPP-b-PPEO), poly (polystyrene)-b-poly (polyacrylic acid) (PPS-b-PPEO), poly (poly (propylene)-b-poly (propylene) A), polydimethylsiloxane-b-polymethacrylic acid (PPDMS-b-PPMAA), polydimethylsiloxane-b-polyvinyl pyrrolidone (PPDMS-b-PPVP), polystyrene-b-poly 4-vinyl pyridine (PPS-b-PP4VP), polystyrene-b-poly 2-vinyl pyridine (PPS-b-PP2VP), polystyrene-b-polydimethylsiloxane-b-polyethylene glycol (PPS-b-PPVP), PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO), poly(PS-b-PPDMS-b-PPEO).

[0013] The synthesis process of the block polymer brush of the present invention refers to patent US20210395463A1. Taking PPS-b-PPEO as an example: the first step is to obtain a norbornene-terminated PS macromonomer by anionic polymerization; the second step is to obtain a norbornene-terminated PEO macromonomer by esterification reaction; the third step is to obtain a block polymer brush by ring-opening metathesis polymerization according to the method of patent US20210395463A1.

[0014] It should be noted that the synthesis methods of different norbornene-terminated macromonomers are determined according to actual production needs, including but not limited to anionic polymerization, cationic polymerization, macromolecular esterification, Click reaction or DA addition.

[0015] Preferably, the mass of the block polymer brush accounts for 15 to 80% of the total mass of the oil-based structural color pigment ink after removing the organic solvent.

[0016] The microphase separation of the block polymer brush in the present invention is the key to self-assembly forming a layered photonic crystal structure, and determines the size of the layered structural domain and the maximum reflection wavelength of the photonic crystal.

[0017] Preferably, the resin or the resin generated from the precursor of the resin includes: polystyrene, polyester, polyvinyl ether, polyether, polyacrylate, polymethacrylate, polyacrylamide, polymethacrylamide, polyurethane, polysiloxane, polyamide, polyethylene terephthalate, phenolic resin, urea resin, alkyd resin, epoxy resin or silicone resin.

[0018] The role of the resin in the present invention is to swell the layered structure of the photonic crystal to adjust the size of the structural domain. The selection of the resin should take into account factors such as the block polymer brush used, subsequent processing performance requirements and subsequent use performance requirements.

[0019] Preferably, the organic solvent comprises: acetone, methanol, ethanol, dimethylformamide, toluene, dichloromethane, n-heptane, cyclohexane, ethyl acetate, butyl acetate, chloroform, ether, anisole, toluene, xylene, benzene, tetrachloromethane, pyridine, hexane, isopropanol, tetrahydrofuran, 1,4-dioxane, styrene, methyl methacrylate or methyl acrylate.

[0020] The organic solvent in the present invention plays the role of adjusting the viscosity of the ink system and uniformly dispersing the components in the system. The primary requirement for selecting an organic solvent is that it can dissolve other components in the system. In addition, the evaporation rate, polarity, viscosity and other characteristics of the organic solvent also affect the final performance of the structural color ink.

[0021] Preferably, the components of the oil-based structural color pigment ink further include an adjusting component.

[0022] More preferably, the regulating component includes: one or more of a plasticizer, a stabilizer, an antioxidant, an anti-aging agent, an anti-UV agent, a degradation agent, a lubricant, a heat stabilizer, a foaming agent, an antistatic agent, a flame retardant, a filler, a coupling agent, a processing modifier, a nucleating agent, an impact modifier, a leveling agent and a defoaming agent.

[0023] The addition of the regulating components in the present invention is to improve the processing performance and use performance of the oily structural color pigment ink, and the addition of some regulating components is also used to adjust the color of the oily structural color pigment ink formula.

[0024] The second technical solution of the present invention is to provide an application of the above-mentioned oily structural color pigment ink in screen printing, spraying, inkjet printing or gravure printing.

[0025] The method for using the oily structural color pigment ink provided by the present invention is as follows:

[0026] The oily structural color pigment ink prepared by the present invention can be used in combination with a traditional pigment coloring method. After the ink is printed on a substrate, a photonic crystal structure covering the surface of the substrate can be obtained through solvent volatilization and post-treatment processes to produce structural colors.

[0027] On the one hand, solvent evaporation increases the viscosity of the structural color ink and improves the adhesion of the ink on the substrate. On the other hand, the evaporation of some solvents can induce the occurrence of the microphase separation process of the block polymer brush and improve the order of the photonic crystal structure. The evaporation process of the solvent can be ambient drying or active drying of the print (for example, using infrared / heat lamps or ultraviolet lamps for active drying). Active drying of prints can quickly dry the ink solution to achieve efficient multiple printing or efficient implementation of other types of post-processing.

[0028] The post-printing treatment methods of the oil-based structural color pigment ink include, but are not limited to, annealing, curing the print, or printing a protective varnish, a transparent coating, or some other surface material on the print. The process of curing the print usually depends on the type of resin used in the formulation, and a stable photonic crystal structure can be obtained by methods including, but not limited to, UV curing, thermal curing, air curing, or near-infrared curing. The purpose of the annealing process is to promote the microphase separation process of the block polymer brush and obtain a more ordered photonic crystal structure.

[0029] The color control method of the oily structural color pigment ink provided by the present invention is as follows:

[0030] There are roughly three methods for color control of structural color inks. First, during the preparation of structural color inks, suitable block polymer brushes (a block polymer brush or a mixture of multiple block polymer brushes), suitable resins, and suitable regulating components can be selected to directly configure structural color inks of desired colors. The process refers to the preparation method of oily structural color pigment inks. Second, two structural color inks of different colors can be pre-mixed to obtain a new desired color with a reflection wavelength between the two. For example, a 1:1 mixture of red and blue structural color inks produces a green ink with a reflection wavelength between the two. Third, the desired color can be obtained through the additive / subtractive principle. For example, multiple structural color inks can be used for multiple printing on the same substrate to obtain multi-layer photonic crystal structures with multiple domain sizes, which can be combined to obtain the desired color. For example, red, blue, and green structural color inks can be used to print a color covering the RGB color gamut.

[0031] The beneficial technical effects of the present invention are as follows:

[0032] The structural color coating obtained by the oily structural color pigment ink provided by the present invention can reflect the ultraviolet-visible-infrared spectrum covering the wavelength range of 200nm-2000nm.

[0033] The photonic crystals in the oily structural color pigment ink provided by the present invention can be combined with a traditional pigment coloring process to obtain a structural color coating by printing.

[0034] The structural color of the oil-based structural color pigment ink provided by the present invention can provide color effects that cannot be produced by current pigments and dyes, and can theoretically realize any spectrum design.

[0035] The oily structural color pigment ink provided by the present invention can provide an enhancement effect through pigments and dyes, and the formed structural color coating is combined with pigments and dyes to achieve a wider range of colors, and a new color gamut is generated by mixing subtractive and additive color mixing theories. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is the LAB color model.

[0037] Figure 2 This is a reflection characteristic curve diagram of the oil-based structural color pigment ink of recipes 1 to 5 in Example 1 after printing and heat treatment.

[0038] Figure 3 This is a reflection characteristic curve diagram of the oil-based structural color pigment ink of recipes 6 to 10 in Example 2 after printing and light treatment.

[0039] Figure 4 This is a reflection characteristic curve diagram of the oil-based structural color pigment ink of recipes 11 to 15 in Example 3 after printing and natural drying. DETAILED DESCRIPTION

[0040] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0041] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0042] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the invention pertains. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention.

[0043] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0044] In an embodiment, the measurement of color values ​​can be performed using the L*a*b* color space. LAB color model (see Figure 1 ), also known as CIELab color space, is a color space defined by the International Commission on Illumination (CIE) in 1976. It is a three-dimensional color space that is widely used for the calculation, comparison and quantitative analysis of various colors. The LAB color model is characterized by being device-independent and reflecting human visual perception more evenly. The LAB color model consists of three components: L*-brightness component, which indicates the lightness and darkness of the color, ranging from 0 (completely black) to 100 (completely white). a*-chromaticity component, which indicates the degree of bias of the color on the red-green axis, with negative values ​​biased toward green and positive values ​​biased toward red. b*-chromaticity component, which indicates the degree of bias of the color on the yellow-blue axis, with negative values ​​biased toward blue and positive values ​​biased toward yellow. The color gamut of the LAB color space is very wide, and it not only includes all the colors that the human eye can perceive, but also includes some theoretical colors. This means that compared with RGB and CMYK color spaces, LAB can describe colors more comprehensively. Color measurement should be performed using a spectrophotometer that conforms to the standards of the International Commission on Illumination (CIE). Equipment should be calibrated regularly to ensure the accuracy of measurement results.

[0045] Example 1

[0046] The oil-based structural color pigment ink was prepared according to the formula in Table 1.

[0047] Table 1

[0048]

[0049] In Table 1, BBCP is specifically PPS-b-PPEO (total molecular weight of about 110W); the phenolic resin precursor is the commercially available Inokai reagent (product number P832682-500g).

[0050] The oil-based structural color pigment inks in formulas 1 to 5 were printed and then heat treated (130° C., 4 h), the color values ​​were measured, and the chromaticity C was calculated using origin. The measurement and calculation results are shown in Table 2.

[0051] Table 2

[0052] formula L a b C 1 166.29 46.53 -140.42 147.93 2 164.05 76.57 -192.77 207.42 3 204.52 77.31 -235.79 248.14 4 209.69 52.26 -215.53 221.77 5 179.20 63.50 -200.26 210.08

[0053] The precise color values ​​of formulations 1 to 5 after heat treatment are shown in Table 2, and the obtained photonic crystals are blue.

[0054] The reflection characteristic curves of the oil-based structural color pigment inks in formulas 1 to 5 after printing and heat treatment are shown in Figure 2 .

[0055] Example 2

[0056] According to the formula in Table 3, an oil-based structural color pigment ink was prepared.

[0057] Table 3

[0058]

[0059] In Table 3, BBCP is specifically PPS-b-PPEO (total molecular weight of about 130W); the epoxy resin precursor is commercial epoxy acrylate agisin 1030; and the triarylsulfonium salt is the photoinitiator.

[0060] The oil-based structural color pigment inks in formulas 6 to 10 were printed and then subjected to light treatment (365 nm ultraviolet light irradiation for 30 min), the color values ​​were measured, and the chromaticity C was calculated using origin. The measurement and calculation results are shown in Table 4.

[0061] Table 4

[0062] formula L a b C 6 158.19 9.88 -117.47 117.88 7 166.29 48.68 -143.46 151.49 8 204.52 75.86 -231.14 243.27 9 179.20 61.26 -204.33 213.31 10 237.37 26.73 -206.67 208.39

[0063] The exact color values ​​of formulations 6 to 10 after light treatment are shown in Table 4, and the resulting photonic crystals are blue.

[0064] The reflection characteristic curves of the oily structural color pigment inks in formulas 6 to 10 after printing and light treatment are shown in FIG. Figure 3 .

[0065] Example 3

[0066] According to the formula in Table 5, an oil-based structural color pigment ink was prepared.

[0067] Table 5

[0068]

[0069]

[0070] In Table 3, BBCP is specifically PPCL-b-PPEO (total molecular weight is about 90W); HT-400 is a leveling agent.

[0071] The oil-based structural color pigment inks in formulas 11 to 15 were printed and dried naturally, the color values ​​were measured, and the chromaticity C was calculated using origin. The measurement and calculation results are shown in Table 6.

[0072] Table 6

[0073] formula L a b C 11 252.41 -22.74 -49.77 54.72 12 278.09 -6.55 -86.40 86.65 13 271.64 -23.99 -61.72 66.22 14 255.86 -4.17 -75.37 75.48 15 295.83 -48.53 -12.15 50.03

[0074] The precise color values ​​of formulations 11 to 15 after printing and drying are shown in Table 6, and the obtained photonic crystals are blue.

[0075] The reflection characteristic curves of the oil-based structural color pigment inks in formulas 11 to 15 after printing and natural drying are shown in Figure 4 .

[0076] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. An oily structural color pigment ink, characterized in that: The components include: at least one block polymer brush, at least one resin or at least one resin precursor, and at least one organic solvent; The blocks in the block polymer brush can undergo microphase separation to form a lamellar domain; The resin or a resin generated from a precursor of the resin is compatible with at least one block of the block polymer brush and has a light transmittance of not less than 50%.

2. The oily structural color pigment ink according to claim 1, characterized in that: The block polymer brush comprises: poly (polystyrene-b-polyethylene glycol), poly (tert-butyl acrylate-b-polyethylene glycol), poly (dimethylsiloxane-b-polyethylene glycol), poly (methyl methacrylate-b-polyethylene glycol), poly (methyl acrylate-b-polyethylene glycol), poly (polyacrylonitrile-b-polyethylene glycol), poly (lactic acid-b-polyethylene glycol), poly (ε-caprolactone-b-polyethylene glycol), poly (polyethylene-b-polyethylene glycol), poly (polypropylene-b-polyethylene glycol), poly (polystyrene-b-polyacrylic acid), poly (poly (polyacrylic acid)), poly (poly (polyacrylic acid)). dimethylsiloxane-b-polymethacrylic acid, polydimethylsiloxane-b-polyvinyl pyrrolidone, polystyrene-b-poly-4-vinyl pyridine, polystyrene-b-poly-2-vinyl pyridine, polystyrene-b-polydimethylsiloxane-b-polyethylene glycol, polystyrene-b-polytert-butyl acrylate-b-polyethylene glycol, polytert-butyl acrylate-b-polydimethylsiloxane-b-polyethylene glycol or polymethyl methacrylate-b-polystyrene-b-polyethylene glycol.

3. The oily structural color pigment ink according to claim 1, characterized in that: The mass of the block polymer brush accounts for 15-80% of the total mass of the oily structural color pigment ink after the organic solvent is removed.

4. The oily structural color pigment ink according to claim 1, characterized in that: The resin or the resin generated from the precursor of the resin includes: polystyrene, polyester, polyvinyl ether, polyether, polyacrylate, polymethacrylate, polyacrylamide, polymethacrylamide, polyurethane, polysiloxane, polyamide, polyethylene terephthalate, phenolic resin, urea resin, alkyd resin, epoxy resin or silicone resin.

5. The oily structural color pigment ink according to claim 1, characterized in that: The organic solvent includes: acetone, methanol, ethanol, dimethylformamide, toluene, dichloromethane, n-heptane, cyclohexane, ethyl acetate, butyl acetate, chloroform, ether, anisole, toluene, xylene, benzene, tetrachloromethane, pyridine, hexane, isopropanol, tetrahydrofuran, 1,4-dioxane, styrene, methyl methacrylate or methyl acrylate.

6. The oily structural color pigment ink according to claim 1, characterized in that: The components of the oil-based structural color pigment ink also include an adjustment component.

7. The oily structural color pigment ink according to claim 6, characterized in that: The regulating components include: one or more of plasticizers, stabilizers, antioxidants, anti-aging agents, UV protection agents, degradation agents, lubricants, heat stabilizers, foaming agents, antistatic agents, flame retardants, fillers, coupling agents, processing modifiers, nucleating agents, impact modifiers, leveling agents and defoaming agents.

8. Use of the oily structural color pigment ink according to any one of claims 1 to 7 in screen printing, spraying, inkjet printing or gravure printing.

Images