Method for realizing structural color patterning based on inorganic salt ink jet regulation and control of double-layer system wrinkles

Abstract

The invention discloses a method for realizing structural color patterning based on inorganic salt ink jet regulation and control of double-layer system wrinkles, and relates to the technical field of optical information patterning, and the method comprises the following steps: stirring and mixing polydimethylsiloxane and a curing agent according to a mass ratio of 10: 1, centrifuging, and curing at 60 DEG C for 8 hours to obtain cured polydimethylsiloxane; the PVA solution is spin-coated on the substrate material at the rotating speed of 500-9500 rpm, and a double-layer system is obtained; carrying out ink-jet printing on an inorganic salt solution on the double-layer system to obtain a double-layer system printed with an ink-jet pattern; and sequentially stretching and releasing the double-layer system printed with the ink-jet pattern to form the pattern with the structural color. Therefore, the technology for realizing the structural color patterning does not need to pay attention to the substrate material, only spin coating and ink jetting are needed to be performed on the substrate material, and the structural color patterning method is simple to operate, practical, low in cost and convenient for large-scale production; the pattern acquisition condition is simple, and the pattern can be released after being stretched.

Description

Technical Field

[0001] The present application relates to the technical field of optical information patterning, and in particular to a method for achieving structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles. Background Art

[0002] At present, with the development of science and technology, surface science plays an increasingly important role in the fields of materials science, optics, biology, etc. Among them, structural color, as a non-pigment color generated by microstructures, has attracted widespread attention due to its unique optical properties and environmental friendliness. Structural colors are widely present in nature, such as butterfly wings and bird feathers. The principle of their generation is mainly based on physical processes such as interference, diffraction or scattering of light. In recent years, researchers have been committed to developing various artificial structural color materials to simulate the structural color phenomenon in nature.

[0003] Among the many methods for preparing structural color materials, the method based on the wrinkling of a polymer double-layer system has attracted much attention due to its simplicity and high efficiency. This method usually involves coating a hard polymer film on a pre-stretched elastic substrate, and then releasing the prestress to produce a periodic wrinkle structure in the hard polymer layer. These wrinkle structures can produce specific structural color effects by changing the propagation path of light. However, traditional wrinkle preparation methods often require complex physical or chemical processing steps, and it is difficult to achieve fine patterning control.

[0004] Compared with the preparation of a gradient double-layer system material and its application in anti-counterfeiting labels in patent CN103578353A, the pattern achieved in this patent requires ultraviolet exposure, the preparation process is complex, the cost is high, and fine pattern control cannot be achieved.

[0005] In order to solve these problems, a method of regulating the wrinkles of a double-layer system based on inorganic salt inkjet printing technology came into being. Summary of the invention

[0006] In order to solve the above-mentioned technical problems existing in the prior art, the present application provides a method for achieving structural color patterning by regulating the wrinkles of a double-layer system based on inorganic salt inkjet, so as to solve the technical problems in the prior art of high preparation process, high cost and inability to achieve fine patterning control.

[0007] In order to achieve the above purpose, the technical solution of the embodiment of the present application is:

[0008] The first aspect of the present application provides a method for realizing structural color patterning by regulating the wrinkles of a double-layer system by inkjet printing of inorganic salts, comprising:

[0009] The polydimethylsiloxane and the curing agent are stirred and mixed in a mass ratio of 10:1, centrifuged, and cured at 60° C. for 8 hours to obtain cured polydimethylsiloxane;

[0010] The cured polydimethylsiloxane is used as a base material, and the PVA solution is spin-coated on the base material at a rotation speed of 500 to 9500 rpm to obtain a double-layer system;

[0011] inkjet printing the inorganic salt solution on the double-layer system to obtain a double-layer system printed with an inkjet pattern;

[0012] The double-layer system printed with the inkjet pattern is stretched and released in sequence to form a structural color pattern; there is a difference between the inkjet area and the non-inkjet area with the structural color pattern, and the structural color pattern disappears under humidity response and reappears under mechanical response.

[0013] In combination with the first aspect, preferably, the centrifugal speed is 5000-8000 rpm, and the centrifugal time is 8-15 min.

[0014] In combination with the first aspect, preferably, the base material has a thickness of 1 to 2 mm.

[0015] In combination with the first aspect, preferably, the added amount of the PVA solution is 50 to 500 μL.

[0016] In combination with the first aspect, preferably, the inorganic salt solution is one or more of LiCl solution and NaCl solution.

[0017] In combination with the first aspect, preferably, the distance between two inkjet points in the inkjet pattern is 10-100 μm.

[0018] In combination with the first aspect, preferably, when inkjet printing is performed, the inkjet pressure is 0-50 bar, the nozzle temperature is 0-50° C., the printing frequency is 0-5000 Hz, the voltage waveform is the preset waveform of the microelectronic printer, and the inkjet voltage is 0-35V.

[0019] In combination with the first aspect, preferably, during the stretching, the stretching pre-strain is 10 to 100%.

[0020] In combination with the first aspect, preferably, there is a difference between the inkjet area and the non-inkjet area having the structural color pattern, including: the inkjet area has no wrinkles, and the non-inkjet area has wrinkles.

[0021] Compared with the prior art, the advantages or beneficial effects of the embodiments of the present application include at least:

[0022] The embodiment of the present application provides a method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles. On the one hand, under a certain ratio, a rigid material is spin-coated on a soft substrate material to form a double-layer system. Due to the mismatch of the elastic modulus of the double-layer system, the surface wrinkles of the double-layer system are generated by releasing the double-layer film after uniaxial stretching; on the other hand, the ions in the inorganic salt solution can destroy the hydrogen bonds between the PVA chains to achieve the regulation of the wrinkles, and the wrinkles will affect the formation of its structural color, resulting in no structural color in the inkjet area and structural color in the non-inkjet area; thirdly, The technology for achieving structural color patterning does not need to pay attention to the base material itself, but only requires spin coating and inkjet printing on the base material. The structural color patterning method is simple to operate, practical, low-cost, and easy to mass produce. Fourthly, the structural color patterning method can achieve patterning simply and quickly, and the conditions for obtaining the pattern are simple, only requiring stretching and then releasing. The structural color patterning method is of a higher level, and patterning can only be achieved when a certain amount of stretching is reached, and the inkjet printing technology can accurately control the printing position of the ink. Fifthly, the method has a high degree of precision and is easy to achieve the disappearance and appearance of the pattern.

[0023] The method provided in the present application can be applied to various fields, such as patterning on device packaging and patterning on labels. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a sample diagram of the double-layer system material in Example 1;

[0025] Figure 2 A sample image of a double-layer system printed with an inkjet pattern provided in Example 1;

[0026] Figure 3 A patterned sample image with a structural color pattern provided in Example 1;

[0027] Figure 4 This is a sample image of patterned elimination of a structural color pattern under humidity response in Example 1;

[0028] Figure 5 This is a sample image of the patterned reproduction of the structural color pattern under mechanical response in Example 1;

[0029] Figure 6 This is a structural diagram of the inkjet area and the non-inkjet area of ​​Example 1 under a microscopic microscope. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0031] In the following description, reference is made to "some embodiments", which describe a subset of all possible embodiments, but it is understood that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict. Unless otherwise defined, all technical and scientific terms used in the embodiments of the present application have the same meaning as those commonly understood by those skilled in the art of the technical field of the embodiments of the present application. The terms used in the embodiments of the present application are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0032] In the following description of this embodiment, the terms "include", "comprising", "having" and "containing" are all open terms, meaning including but not limited to.

[0033] It should be noted that all raw materials / reagents in the examples of the present application can be purchased on the market or prepared according to conventional methods well known to those skilled in the art; the term "and / or" in the examples of the present application is only used to describe the association relationship between associated objects, indicating that three relationships may exist, for example, A and / or B means the existence of A alone, B alone, and A and B at the same time, among which A and B can be singular or plural, and the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0034] In the following description of this embodiment, the term "at least one" refers to one or more, and "plurality" refers to two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c", can all represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0035] Those skilled in the art should understand that in the following description of the embodiments of the present application, the order of serial numbers does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0036] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0037] Those skilled in the art will appreciate that the numerical ranges in the examples of the present application are to be understood as also specifically disclosing each intermediate value between the upper and lower limits of the range. Each smaller range between the intermediate values ​​in any stated value and stated range and any other stated value or intermediate value in the range is also included in the present application. The upper and lower limits of these smaller ranges may be independently included or excluded in the scope.

[0038] Unless otherwise stated, the technical / scientific terms used herein have the same meanings as those generally understood by those skilled in the art in the field described in the present application. Although the present application only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the embodiments or test cases of the present application. All documents mentioned in this specification are generally incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of the present application shall prevail.

[0039] It should be noted that all raw materials and / or reagents in the examples of the present application are purchased on the market or prepared according to conventional methods well known to those skilled in the art.

[0040] In a first aspect, the present application provides a method for realizing structural color patterning by regulating the wrinkles of a double-layer system by inkjet printing with inorganic salts, comprising:

[0041] The polydimethylsiloxane and the curing agent are stirred and mixed in a mass ratio of 10:1, centrifuged, and cured at 60° C. for 8 hours to obtain cured polydimethylsiloxane;

[0042] The cured polydimethylsiloxane is used as a base material, and the PVA solution is spin-coated on the base material at a rotation speed of 500 to 9500 rpm to obtain a double-layer system;

[0043] inkjet printing the inorganic salt solution on the double-layer system to obtain a double-layer system printed with an inkjet pattern;

[0044] The double-layer system printed with the inkjet pattern is stretched and released in sequence to form a structural color pattern; there is a difference between the inkjet area and the non-inkjet area with the structural color pattern, and the structural color pattern disappears under humidity response and reappears under mechanical response.

[0045] The embodiment of the present application provides a method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles. On the one hand, under a certain ratio, a rigid material is spin-coated on a soft substrate material to form a double-layer system. Due to the mismatch of the elastic modulus of the double-layer system, the surface wrinkles of the double-layer system are generated by releasing the double-layer film after uniaxial stretching; on the other hand, the ions in the inorganic salt solution can destroy the hydrogen bonds between the PVA chains to achieve the regulation of the wrinkles, and the wrinkles will affect the formation of its structural color, resulting in no structural color in the inkjet area and structural color in the non-inkjet area; thirdly, The technology for achieving structural color patterning does not need to pay attention to the base material itself, but only requires spin coating and inkjet printing on the base material. The structural color patterning method is simple to operate, practical, low-cost, and easy to mass produce. Fourthly, the structural color patterning method can achieve patterning simply and quickly, and the conditions for obtaining the pattern are simple, only requiring stretching and then releasing. The structural color patterning method is of a higher level, and patterning can only be achieved when a certain amount of stretching is reached, and the inkjet printing technology can accurately control the printing position of the ink. Fifthly, the method has a high degree of precision and is easy to achieve the disappearance and appearance of the pattern.

[0046] The present application provides a method for realizing structural color patterning by regulating the wrinkles of a double-layer system based on inorganic salt inkjet. First, a soft substrate material is synthesized, and a layer of rigid material is spin-coated on the substrate. Due to the different properties of the double-layer materials, the elastic modulus of the double-layer system does not match, and the surface wrinkles are generated by uniaxial stretching and subsequent release of the double-layer film. It is worth noting that in the double-layer system, the wrinkles are regulated by an inorganic salt solution, and the pattern used for inkjet is formed by the ions in the inorganic salt solution destroying the hydrogen bonds between the PVA chains, thereby affecting the formation of its wrinkles. Because the wrinkles will affect its structural color, no structural color is generated in the inkjet area, while there is structural color in the non-inkjet area. This is the main reason why patterning can be achieved by forming a pattern with structural color.

[0047] It should be noted that the purpose of the centrifugal treatment is to remove bubbles generated when polydimethylsiloxane reacts with the curing agent.

[0048] It should be noted that the cured polydimethylsiloxane sample needs to be cut into samples with a size of 2.5 cm×2.5 cm.

[0049] It should be noted that the concentration of the PVA solution is 6-10 wt %, and the PVA model is 1788.

[0050] It should be noted that the device used for inkjet printing is a microelectronic printer.

[0051] In a specific embodiment, the centrifugal speed of the embodiment of the present application is preferably 5000-8000 rpm, and the centrifugal time is preferably 8-15 min.

[0052] When the centrifugal speed is too high, it may cause excessive stirring of the mixture, resulting in heating of the mixture or unnecessary stress, affecting the material properties. When the centrifugal speed is too low, it may affect the incomplete removal of bubbles, which may cause defects inside the material after curing. In addition, sufficient centrifugal time can ensure that the PDMS main agent and curing agent are thoroughly mixed, avoiding inconsistent material properties due to uneven mixing.

[0053] In a specific embodiment, the thickness of the base material in the embodiment of the present application is preferably 1 to 2 mm.

[0054] Among them, when the substrate is relatively too thick, its bending rigidity is large and it is not easy to deform. The stress transfer efficiency of the film-substrate interface will be reduced, resulting in the need for a larger external force to cause wrinkles in the film. The formation of wrinkles may be inhibited, so that wrinkles can only be observed under a larger tensile strain. When the substrate is thin, due to its easy deformation, the shape and position of the wrinkles may change dynamically with the change of external force, and the instability and variability of the wrinkles increase.

[0055] In a specific embodiment, the amount of the PVA solution added in the embodiment of the present application is preferably 50 to 500 μL.

[0056] If the amount of PVA added is too much, the top film thickness will be too thick, thus affecting the formation of structural color. If the amount of PVA added is too little, the edge of the top film cannot be spin-coated.

[0057] In a specific embodiment, the inorganic salt solution in the embodiment of the present application is preferably one of a LiCl solution and a NaCl solution.

[0058] In a specific embodiment, the distance between two inkjet points in the inkjet pattern of the embodiment of the present application is preferably 10-100 μm.

[0059] In a specific embodiment, when performing inkjet printing in the embodiment of the present application, the inkjet pressure is preferably 0-50 bar, the nozzle temperature is preferably 0-50° C., the printing frequency is preferably 0-5000 Hz, the voltage waveform is preferably the preset waveform of the microelectronic printer, and the inkjet voltage is 0-35V.

[0060] Among them, a frequency that is too high will cause the ink to come out too quickly, and a frequency that is too low will cause the ink to come out too slowly. Both too high and too low frequencies will affect the patterning effect printed on the double-layer system.

[0061] In a specific embodiment, when stretching is performed in the embodiment of the present application, the stretching pre-strain is preferably 10 to 100%.

[0062] In a specific embodiment, there is a difference between the inkjet area and the non-inkjet area with the structural color pattern in the embodiment of the present application. Preferably, the inkjet area has no wrinkles, while the non-inkjet area has wrinkles.

[0063] The advantage of the method provided in this application is that it is a non-contact operation mode, which can quickly and accurately generate complex structural color patterns on the substrate. In addition, by adjusting the type and concentration of inorganic salts, the wrinkle period and depth can be controlled, thereby adjusting the hue, brightness and other optical properties of the structural color. Therefore, the method of regulating the wrinkles of the double-layer system based on inorganic salt inkjet provides new ideas and technical support for the preparation and application of structural color materials.

[0064] The technical method of the present application will be further described below in conjunction with specific embodiments.

[0065] Example 1

[0066] This embodiment 1 provides a method for realizing structural color patterning by regulating the wrinkles of a double-layer system based on inorganic salt inkjet, and the specific steps are as follows:

[0067] (1) 18.3 g of the main agent polydimethylsiloxane and 1.83 g of the curing agent were mixed in a centrifuge tube, stirred for 10 min, and centrifuged at a centrifuge speed of 5000 rpm for 10 min to remove bubbles generated during stirring. After centrifugation, the mixture was poured into a 13 cm × 13 cm culture dish, cured at 60°C for 8 h, and cut into samples of 2.5 cm × 2.5 cm in size to obtain a polydimethylsiloxane substrate.

[0068] (2) 1.6 g of PVA was dissolved in 18.4 mL of pure water, and 130 μL of the prepared PVA solution was spin-coated on a polydimethylsiloxane substrate at a speed of 7500 rpm for 60 s to obtain a double-layer system.

[0069] (3) 2 mL of 40 wt% inorganic salt solution was loaded into the inkjet ink bag, the inkjet pressure was 0, the nozzle temperature was 25° C., the printing frequency was 4000 Hz, the voltage waveform was the preset waveform of the microelectronic printer, and the inkjet voltage was 0-35 V.

[0070] (4) The sample is clamped in a uniaxially stretchable fixture, and then stretched with a pre-strain of 10 to 100% for 0 to 30 minutes, and then the sample is restored to its original shape, thereby forming a pattern with structural color.

[0071] In order to verify the patterning performance of the structural color pattern, the structural color pattern was characterized. The characterization results are as follows: Figures 1 to 6 shown. Figure 1 This is a sample picture of the double-layer system material in Example 1. Figure 2 Sample image of a two-layer system printed with an inkjet pattern provided in Example 1. Figure 3 This is a patterned sample image with a structural color pattern provided in Example 1. Figure 4 This is a sample image of Example 1 with patterned elimination of a structural color pattern in response to humidity. Figure 5 This is a sample image of Example 1 with patterned reproduction of structural color patterns under mechanical response. Figure 6 This is a structural diagram of the inkjet area and the non-inkjet area of ​​Example 1 under a microscopic microscope.

[0072] according to Figure 1 It can be seen that the double-layer system material obtained in Example 1 is in a transparent state without any mechanical response and does not produce any structural color.

[0073] according to Figure 2 It can be seen that in the two-layer system sample printed with the inkjet pattern obtained in Example 1, it is difficult to observe the pattern when no structural color is formed.

[0074] according to Figure 3 It can be seen that in the sample with structural color patterning obtained in Implementation Case 1, its response mode is relatively simple, and only mechanical response is required to obtain its result graph.

[0075] according to Figure 4 It can be seen that the pattern with structural color obtained in Example 1 is exhaled to increase the influence of humidity on the wrinkles of the sample, so that the pattern with structural color of the sample disappears, and then stretched with a pre-strain of 10 to 100%, and then the sample is restored to its original shape, thereby realizing the pattern with structural color.

[0076] The results obtained refer to Figure 5 , the above-mentioned implementation case 5 was repeated for 5 times, and the patterning with structural color pattern and the erasing of the patterning with structural color were realized respectively. This shows that the patterning with structural color produced as a double-layer system film in the present application can be repeatedly realized, that is, after the patterning with structural color disappears by high humidity, the patterning with structural color can be realized again, thereby realizing the repeated use of pattern labeling.

[0077] according to Figure 6 It can be seen that no wrinkles are formed in the inkjet area, while wrinkles are formed in the non-inkjet area, thereby forming a pattern with structural colors.

[0078] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for achieving structural color patterning based on inorganic salt inkjet control of double-layer system wrinkles, characterized in that: include: The polydimethylsiloxane and the curing agent are stirred and mixed in a mass ratio of 10:1, centrifuged, and cured at 60° C. for 8 hours to obtain cured polydimethylsiloxane; The cured polydimethylsiloxane is used as a base material, and the PVA solution is spin-coated on the base material at a rotation speed of 500 to 9500 rpm to obtain a double-layer system; inkjet printing the inorganic salt solution on the double-layer system to obtain a double-layer system printed with an inkjet pattern; The double-layer system printed with the inkjet pattern is stretched and released in sequence to form a structural color pattern; there is a difference between the inkjet area and the non-inkjet area with the structural color pattern, and the structural color pattern disappears under humidity response and reappears under mechanical response.

2. The method for realizing structural color patterning based on inorganic salt inkjet control of double-layer system wrinkles according to claim 1, characterized in that: The centrifugal speed is 5000-8000 rpm, and the centrifugal time is 8-15 min.

3. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: The thickness of the base material is 1 to 2 mm.

4. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: The amount of the PVA solution added is 50 to 500 μL.

5. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: The inorganic salt solution is one or more of LiCl solution and NaCl solution.

6. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: The distance between two inkjet points in the inkjet pattern is 10-100 μm.

7. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: When performing inkjet printing, the inkjet pressure is 0-50 bar, the nozzle temperature is 0-50° C., the printing frequency is 0-5000 Hz, the voltage waveform is the preset waveform of the microelectronic printer, and the inkjet voltage is 0-35V.

8. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: During the stretching, the stretching pre-strain is 10 to 100%.

9. The method for realizing structural color patterning based on inorganic salt inkjet-controlled double-layer system wrinkles according to claim 1, characterized in that: There is a difference between the inkjet area and the non-inkjet area having the structural color pattern, including: the inkjet area has no wrinkles, and the non-inkjet area has wrinkles.

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