Phase-patterned liquid crystal elastic body

Abstract

The phase-patterned liquid crystal elastomer according to an embodiment of the present invention includes: a first region including liquid crystals; and a second region which is adjacent to the first region, includes liquid crystals, and includes a phase different from that of the first region.

Description

Phase-patterned liquid crystal elastomer

[0001] The present disclosure relates to a liquid crystal elastomer and a method for producing the same.

[0002]

[0003] Previous studies on liquid crystal elastomers could only produce a specific phase (nematic-monodomain) of liquid crystal elastomers through stretching and UV-based photocrosslinking.

[0004] These approaches to studying liquid crystal elastomers were only able to produce a single simple phase in the liquid crystal elastomer, and local control was impossible and reversibility was absent.

[0005] Due to the limitations of such previous studies, research on liquid crystal elastomers has mainly focused on theoretical studies in the fields of soft actuators and soft robots, and has not been able to fully utilize the potential of liquid crystal elastomers to express their inherent optical and mechanical properties.

[0006]

[0007] The embodiments of the present invention are intended to implement various potentials of liquid crystal elastomers as materials by introducing a technology for freely controlling and fixing the image of a local region of a liquid crystal elastomer and reversibly restoring it.

[0008] The present invention aims to expand the scope of liquid crystal elastomer research currently being actively conducted in the field of soft robotics and to promote diverse applications.

[0009] However, the purpose of the present invention is not limited to the above-described contents.

[0010]

[0011] A phase-patterned liquid crystal elastomer according to one aspect of the present disclosure comprises: a first region comprising liquid crystal; and a second region adjacent to the first region, comprising liquid crystal and comprising a phase different from that of the first region.

[0012] In one embodiment, the first region may comprise a nematic phase and the second region may comprise an isotropic phase.

[0013] In one embodiment, the first region may comprise a polydomain.

[0014] In one embodiment, the second region may be capable of reversibly changing into a polydomain of nematic phase.

[0015] According to one embodiment, the liquid crystal elastomer may include a guest molecule capable of dynamic crosslinking.

[0016] In one embodiment, the guest molecule may comprise one or more selected from the group consisting of RM257, EDDET, PETMP, and MBTA.

[0017] In one embodiment, the second region may have a width of 0.1 μm to 20 μm and may be patterned by laser irradiation.

[0018] In one embodiment, the first region and the second region may have different transparency values.

[0019] In one embodiment, the boundary between the first region and the second region may be defined by a directional line.

[0020] In one embodiment, the first region and the second region may become indistinguishable depending on an external stimulus, and then another boundary may be formed to divide them into another first region and a second region.

[0021] According to one embodiment, the third region further includes a phase different from the first region and the second region; wherein the third region may have a phase different from the first region and the second region among regions having a polydomain, a monodomain, and an isotropic phase.

[0022]

[0023] A device including a liquid crystal elastomer according to another aspect of the present invention includes a liquid crystal elastomer capable of generating a pattern by distinguishing a plurality of regions having different phases from each other, each of the plurality of regions being capable of reversibly changing transparency in response to an external stimulus, and the liquid crystal elastomer may be the liquid crystal elastomer of the above-described embodiment.

[0024] In one embodiment, the device may be equipped with an information recognition security pattern.

[0025] In one embodiment, the device is one or more of a wearable device, a security device, and a soft robot, and may be capable of changing the pattern through human body temperature.

[0026]

[0027] In one embodiment, the device may be capable of deleting and regenerating the pattern.

[0028]

[0029] A method for manufacturing a phase-patterned liquid crystal elastomer according to another aspect of the present invention comprises the steps of: preparing a liquid crystal elastomer; irradiating a laser to a portion of the liquid crystal elastomer; and cooling the laser-irradiated liquid crystal elastomer; wherein the liquid crystal elastomer may be the liquid crystal elastomer of the above-described embodiment.

[0030] According to one embodiment, the method may further include a step of heating the liquid crystal elastic body to a predetermined temperature.

[0031] According to one embodiment, the step of preparing the liquid crystal elastomer includes synthesizing the liquid crystal elastomer by introducing at least one selected from the group consisting of RM257, 1,4-bis(4-(3-acryloyloxypropoxy)benzoyloxy)-2-methylbenzene; EDDET, 2,2'-(ethylenedioxy)diethanethiol; PETMP and pentaerythritol tetrakis(3-mercaptopropionate); and MBTA, and the step of irradiating a laser to a portion of the liquid crystal elastomer may include changing the phase of the portion irradiated with the laser as at least a portion of the liquid crystal elastomer is heated to a temperature of 30 to 100 degrees.

[0032] According to one embodiment, the method may further include a step of applying a physical external force pulling the liquid crystal elastomer in at least one direction to deform a portion of the liquid crystal elastomer to elongate it.

[0033] According to one embodiment, the method may further include a step of irradiating a laser again to a portion of the liquid crystal elastic body on which the patterning is formed to erase the previously generated pattern, and irradiating a laser again to a specific portion.

[0034]

[0035] The present invention, unlike existing liquid crystal elastomer control technologies, can also implement an isotropic phase in the liquid crystal elastomer by adding an intermediate heating process, and has the effect of locally controlling the phase change in a specific region by using a high-resolution laser for secondary crosslinking. Furthermore, by introducing the principle of dynamic crosslinking within the liquid crystal elastomer, it has the effect of adding reversibility to the process, making it possible to restore the original state even after fixing it to a specific phase.

[0036] Embodiments of the present invention are expected to further expand the scope of liquid crystal elastomer research currently underway in the field of soft robotics. Specifically, the embodiments of the present invention can be applied to soft robots and other devices due to their ability to perform localized patterning at the micro level. Furthermore, by enabling control of the mechanical properties of liquid crystal elastomers, their application to wearable devices is also possible.

[0037] However, the effects of the present invention are not limited to the effects described above, but include all effects naturally implemented due to the various configurations proposed in the present invention.

[0038]

[0039] FIG. 1 is a graphic image showing a change in properties of a liquid crystal elastomer according to one embodiment of the present invention through laser irradiation and thermal stimulation response.

[0040] FIG. 2 is an image showing a phase control process of a liquid crystal elastomer according to one embodiment of the present invention, and is an example showing a method for controlling a specific region of a liquid crystal elastomer to an intended phase by heating the temperature and then irradiating a laser.

[0041] FIG. 3 is an enlarged image showing a process in which a reversible phase change occurs after selective phase patterning in a phase-patterned liquid crystal elastomer according to one embodiment of the present invention.

[0042] FIG. 4 is an image illustrating a process of patterning a phase in a liquid crystal elastomer according to one embodiment of the present invention and then reversibly erasing the patterning, and the arrangement of liquid crystals in the liquid crystal elastomer at each step is illustrated according to the order of each image.

[0043] FIG. 5 is an image (FIG. 5a) showing a process of forming polydomain, monodomain, and isotropic phases on a single plane in a liquid crystal elastomer according to one embodiment of the present invention, and a photographic image (FIG. 5b) actually implementing the process.

[0044] FIG. 6 is an example of monomers included in a liquid crystal elastomer according to one embodiment of the present invention, and structural formulas of RM257, EDDET, PETMP, and MBTA molecules are shown.

[0045] FIG. 7 is a photographic image of an experiment in which a liquid crystal elastomer according to one embodiment of the present invention is in a polydomain state - some areas are changed to an isotropic phase, and then some areas among the areas where the isotropic phase is formed are reversibly formed into a polydomain area (r-Poly).

[0046] FIG. 8 is a photographic image showing an experiment in which a liquid crystal elastomer according to one embodiment of the present invention was patterned to form an animal image pattern, then erased, and then a barcode image pattern was formed and then erased again.

[0047] FIG. 9a is a graph showing the phase change and the change in transmittance of a liquid crystal elastomer manufactured according to one embodiment of the present invention when the temperature (T) changes over time, and FIG. 9b is a graph showing that the phase change and the change in transmittance continue to be stably formed even when the heating (40°C) and cooling (20°C) cycles are repeated up to 1000 cycles.

[0048] FIG. 10 is an image illustrating a process of selectively applying polydopamine (PDA) coating to some areas to simultaneously utilize patterning and physical motion in a liquid crystal elastomer according to one embodiment of the present invention, then patterning a QR code in one area and irradiating an IR lamp in another area to change the physical shape of the liquid crystal elastomer.

[0049] FIG. 11 is an image illustrating an example of an application that applies a liquid crystal elastic body according to one embodiment of the present invention as a device.

[0050] FIG. 12 is an image illustrating another example of an application in which a liquid crystal elastic body according to one embodiment of the present invention is applied as a device.

[0051]

[0052] The embodiments of the present invention are provided for the purpose of illustrating the technical concept of the present invention. The scope of the rights of the present invention is not limited to the embodiments presented below or the specific descriptions of these embodiments.

[0053] All technical and scientific terms used in this invention, unless otherwise defined, have the meanings commonly understood by those of ordinary skill in the art to which this invention pertains. All terms used in this invention have been selected for the purpose of more clearly explaining the invention and are not intended to limit the scope of the rights provided for in this invention.

[0054] Expressions such as “comprising,” “having,” and the like used in the present invention should be understood as open-ended terms that imply the possibility of including other embodiments, unless otherwise stated in the phrase or sentence in which the expression is included.

[0055] The singular expressions described in the present invention may include plural meanings unless otherwise stated, and this also applies to the singular expressions described in the claims.

[0056] Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. Furthermore, in the description of the embodiments below, duplicate descriptions of identical or corresponding components may be omitted. However, even if descriptions of components are omitted, this does not mean that such components are not included in any embodiment.

[0057]

[0058] The present invention aims to develop and patent a technology capable of locally controlling the phase of a liquid crystal elastomer through local UV laser irradiation in a heated or tensile state. According to embodiments of the present invention, in the process of using a liquid crystal elastomer, the phase of the region of the liquid crystal elastomer irradiated with the laser can be freely controlled by adjusting the laser process parameters (laser power, scanning speed), thereby controlling various optical and mechanical properties.

[0059] The present invention goes beyond the conventionally known control technologies for liquid crystal elastomers and enables reversible implementation of multi-phase and various patterning in grayscale form.

[0060] According to an embodiment of the present invention, the phase can be controlled by performing secondary crosslinking in a tensioned or heated state using a liquid crystal elastomer that is not completely crosslinked.

[0061] The above liquid crystal elastomer can be fixed in a polydomain nematic phase when irradiated with a laser in the absence of thermal stimulation immediately after synthesis.

[0062] Alternatively, if the above liquid crystal elastic body is stretched immediately after synthesis, it becomes a monodomain nematic phase, and if a laser is irradiated at this time, this phase can be fixed.

[0063] Alternatively, if the liquid crystal elastomer is heated and irradiated with a laser immediately after synthesis, the isotropic phase is fixed.

[0064] In the above embodiment, each phase has different optical and mechanical properties and can be controlled as needed.

[0065]

[0066] This phase fixation phenomenon occurs by fixing the molecules of the liquid crystal elastomer to a specific phase through secondary cross-linking using laser irradiation.

[0067] In this case, in embodiments of the present invention, this fixation effect can be reversibly released by introducing a guest molecule capable of inducing dynamic crosslinking. In this way, the patterned phase of the liquid crystal elastomer to which the guest molecule has been introduced can reversibly return to its initial polydomain state.

[0068]

[0069] Below, various embodiments of the present invention are described separately.

[0070]

[0071] Phase-patterned liquid crystal elastomer

[0072] A phase-patterned liquid crystal elastomer according to one aspect of the present disclosure comprises: a first region comprising liquid crystal; and a second region adjacent to the first region, comprising liquid crystal and comprising a phase different from that of the first region.

[0073] In the present invention, the liquid crystal elastomer is not limited to a liquid crystal elastomer made of a special material.

[0074] The above liquid crystal elastic body may include a plurality of regions including different phases, and the different phases at this time include not only the distinction between polydomain and monodomain, but also the isotropic phase and nematic phase that exhibit isotropy.

[0075] In one embodiment, the first region may comprise a nematic phase and the second region may comprise an isotropic isotropic phase.

[0076] In one embodiment, the first region may comprise a polydomain.

[0077] In one embodiment, the second region may be capable of reversibly changing into a polydomain of nematic phase.

[0078] According to one embodiment, the liquid crystal elastomer may include a guest molecule capable of dynamic crosslinking.

[0079] In one embodiment, the guest molecule may comprise one or more selected from the group consisting of RM257, EDDET, PETMP, and MBTA.

[0080] In one embodiment, the second region may have a width of 0.1 μm to 20 μm and may be patterned by laser irradiation.

[0081] In one embodiment, the first region and the second region may have different transparency values.

[0082] In one embodiment, the boundary between the first region and the second region may be defined by a directional line.

[0083] In one embodiment, the first and second regions may become indistinguishable in response to an external stimulus, and then a new boundary may be formed, resulting in another first and second region. This reversible change can be stably performed for approximately 1,000 cycles or more.

[0084] According to one embodiment, the third region further includes a phase different from the first region and the second region; wherein the third region may have a phase different from the first region and the second region among regions having a polydomain, a monodomain, and an isotropic phase.

[0085]

[0086] A device including a liquid crystal elastomer according to another aspect of the present invention includes a liquid crystal elastomer capable of generating a pattern by distinguishing a plurality of regions having different phases from each other, each of the plurality of regions being capable of reversibly changing transparency in response to an external stimulus, and the liquid crystal elastomer may be the liquid crystal elastomer of the above-described embodiment.

[0087] In one embodiment, the device may be equipped with an information recognition security pattern.

[0088] In one embodiment, the device is one or more of a wearable device, a security device, and a soft robot, and may be capable of changing the pattern through human body temperature.

[0089]

[0090] In one embodiment, the device may be capable of deleting and regenerating the pattern.

[0091]

[0092] A method for manufacturing a phase-patterned liquid crystal elastomer according to another aspect of the present invention comprises the steps of: preparing a liquid crystal elastomer; irradiating a laser to a portion of the liquid crystal elastomer; and cooling the laser-irradiated liquid crystal elastomer; wherein the liquid crystal elastomer may be the liquid crystal elastomer of the above-described embodiment.

[0093] According to one embodiment, the method may further include a step of heating the liquid crystal elastic body to a predetermined temperature.

[0094] According to one embodiment, the step of preparing the liquid crystal elastomer includes synthesizing the liquid crystal elastomer by introducing at least one selected from the group consisting of RM257, 1,4-bis(4-(3-acryloyloxypropoxy)benzoyloxy)-2-methylbenzene; EDDET, 2,2'-(ethylenedioxy)diethanethiol; PETMP and pentaerythritol tetrakis(3-mercaptopropionate); and MBTA, and the step of irradiating a laser to a portion of the liquid crystal elastomer may include changing the phase of the portion irradiated with the laser as at least a portion of the liquid crystal elastomer is heated to a temperature of 30 to 100 degrees.

[0095] According to one embodiment, the method may further include a step of applying a physical external force pulling the liquid crystal elastomer in at least one direction to deform a portion of the liquid crystal elastomer to elongate it.

[0096] According to one embodiment, the method may further include a step of irradiating a laser again to a portion of the liquid crystal elastic body on which the patterning is formed to erase the previously generated pattern, and irradiating a laser again to a specific portion.

[0097]

[0098]

[0099] Hereinafter, an embodiment of the stretchable electronic device according to the present disclosure, its performance test, and its potential for use in various applications are described in detail through drawings and examples.

[0100]

[0101] <Example>

[0102] The present inventors manufactured a liquid crystal elastic body having a phase pattern in various forms according to the manufacturing method described above as an example according to the present disclosure and tested the applicability thereof.

[0103]

[0104] Synthesis of liquid crystal elastomers

[0105] The LCE precursor was composed of acrylate monomers RM257 and MBTA, thiol monomers EDDET and PETMP, toluene solvent, photoinitiators Irgacure 651 and Irgacure 819, inhibitor BHT, and catalyst DPA. The acrylate / thiol ratio was maintained at 1.1:1.

[0106] Specifically, RM257 and MBTA were dissolved in toluene at a molar ratio of 9:1 at 80°C for 3 minutes, followed by the addition of EDDET and PETMP at a molar ratio of 20:1. Subsequently, 1 wt% of Irgacure 651, 1 wt% of Irgacure 819, and 0.2 wt% of BHT were introduced, and a catalytic amount of DPA diluted in toluene at a ratio of 1:50 was mixed before polymerization.

[0107] After thorough mixing at 80°C and subsequent degassing, the liquid crystal elastomer precursor was obtained.

[0108] The glass slides were sequentially rinsed with ethanol and acetone, dried using an air gun, and then washed. The slides were plasma treated for 1 minute, and a 5 wt% PAA solution in deionized water was added and spin-coated at 3,000 rpm for 60 seconds to form a sacrificial layer.

[0109] After a 5-minute baking step at 100°C, 500 μm-thick polyimide tape was attached to the side ends of the slide as spacers. The liquid crystal elastomer precursor was then carefully poured onto the glass slide, excess precursor was removed, and the slide was dried overnight at room temperature to enable the thiol-acrylate Michael addition reaction, forming a liquid crystal elastomer in an intermediate polydomain state.

[0110] The slide was then transferred to a vacuum chamber and maintained at 80°C for 12 hours to promote evaporation of residual toluene, and after laser treatment, the sacrificial layer was dissolved in deionized water to produce a free-standing liquid crystal elastomer film with an estimated thickness of approximately 400 μm.

[0111]

[0112] Experiments to verify various phase changes using liquid crystal elastomer films

[0113] FIG. 1 is a graphic image showing a change in properties of a liquid crystal elastomer according to one embodiment of the present invention through laser irradiation and thermal stimulation response.

[0114] The liquid crystal elastomer according to the embodiment of the present invention exists in a polydomain nematic phase immediately after synthesis, and can be transformed into a monodomain nematic phase when stretched. Furthermore, when heated, it becomes an isotropic phase of an isotropic phase. At this time, it was confirmed that each phase has different optical and mechanical properties.

[0115] At this time, the scale bar of Fig. 1 is 10 mm, and through this, it can be confirmed that the width of the patterning proposed in the embodiment of the present invention can be sufficiently implemented up to a scale of several micrometers.

[0116]

[0117] According to an embodiment of the present invention, when manufacturing a liquid crystal elastomer, the liquid crystal elastomer can be synthesized in a state that is not completely cross-linked. In this case, according to one embodiment, the phase can be controlled by performing secondary cross-linking on the liquid crystal elastomer through laser irradiation. If the laser irradiation is performed in a state without mechanical or thermal stimulation immediately after synthesis, the liquid crystal elastomer is fixed in a polydomain state, and if the laser irradiation is performed in a stretched state, a monodomain state can be formed. In addition, if the laser irradiation is performed in a heated state, a liquid crystal elastomer having an isotropic phase with transparent properties can be realized.

[0118]

[0119] FIG. 2 is an image showing a phase control process of a liquid crystal elastomer according to one embodiment of the present invention, and is an example showing a method for controlling a specific region of a liquid crystal elastomer to an intended phase by heating the temperature and then irradiating a laser.

[0120] Figure 2a introduces a method for forming a pattern by irradiating a laser on a suitably heated liquid crystal elastomer and fixing the laser-irradiated area in an isotropic phase. Figure 2b introduces a process for reversibly restoring the liquid crystal elastomer to its original polydomain state by heating the patterned liquid crystal elastomer to a high temperature and irradiating it with a high-energy laser.

[0121] FIG. 3 is an enlarged image showing a process in which a reversible phase change occurs after selective phase patterning in a phase-patterned liquid crystal elastomer according to one embodiment of the present invention.

[0122] As illustrated in Fig. 3, a local region irradiated with a laser in a polydomain state is transformed into an isotropic phase as dynamic crosslinking of the liquid crystal elastomer occurs, and this phase change may be accompanied by optical and mechanical changes. That is, since the liquid crystal elastomer in the laser-irradiated region has low transparency, a pattern that is distinguishable even with the naked eye may be formed in the liquid crystal elastomer. Thereafter, the liquid crystal elastomer on which the patterning is formed may be re-irradiated with a stronger energy laser to return from the isotropic phase to a polydomain state and regain its original transparency.

[0123]

[0124] FIG. 4 is an image illustrating a process of patterning a phase in a liquid crystal elastomer according to one embodiment of the present invention and then reversibly erasing the patterning, and the arrangement of liquid crystals in the liquid crystal elastomer at each step is illustrated according to the order of each image.

[0125] Through this, it is possible to understand how the phase patterning and restoration of the liquid crystal elastomer according to one embodiment of the present invention are formed at each process step.

[0126]

[0127] FIG. 5 is an image (FIG. 5a) showing a process of forming polydomain, monodomain, and isotropic phases on a single plane in a liquid crystal elastomer according to one embodiment of the present invention, and a photographic image (FIG. 5b) actually implementing the process.

[0128]

[0129] FIG. 6 is an example of monomers included in a liquid crystal elastomer according to one embodiment of the present invention, and structural formulas of RM257, EDDET, PETMP, and MBTA molecules are shown.

[0130] The above molecules may function as RAFT reagents. The above molecules may provide an effect of improving the stability of thermal response characteristics during the process of forming a pattern of a liquid crystal elastomer.

[0131] The RAFT reaction, which has recently emerged as a promising technology in the field of liquid crystal elastomers, proceeds by forming an intermediate state of monomer molecules, followed by chain fragmentation and reformation. This reaction has the advantage of maintaining the original function and connectivity of the molecules. This reaction can aid in the reversible patterning of liquid crystal elastomers, as intended in embodiments of the present invention.

[0132] Although the inventors of the present invention prepared a liquid crystal elastomer using the monomers shown in FIG. 6 in some examples, the liquid crystal elastomer proposed in the present invention does not necessarily have to be synthesized using the monomers shown in FIG. 5.

[0133]

[0134] FIG. 7 is a photographic image of an experiment in which a liquid crystal elastomer according to one embodiment of the present invention is in a polydomain state - some areas are changed to an isotropic phase, and then some areas among the areas where the isotropic phase is formed are reversibly formed into a polydomain area (r-Poly).

[0135] FIG. 8 is a photographic image showing an experiment in which a liquid crystal elastomer according to one embodiment of the present invention was patterned to form a leopard image pattern, then erased, and then a QR code image pattern was formed and then erased again.

[0136] In this process, the inventors of the present invention considered that the photoinitiator would be consumed during the writing and erasing processes, and therefore, after the erasing process, the liquid crystal elastomer film of FIG. 8 was swollen in a toluene solution containing 2 wt% of the photoinitiator for 24 hours. Then, the LCE was swollen by natural vacuum drying for 72 hours, and then the writing process was performed again to secure the QR code image of FIG. 8.

[0137] The images in Figures 7 and 8 suggest that a wide variety of applications can be derived by exploiting the difference in transparency and reversible reaction between the polydomain and the isotropic phase.

[0138]

[0139] FIG. 9a is a graph showing the phase change and the change in transmittance of a liquid crystal elastomer manufactured according to one embodiment of the present invention when the temperature (T) changes over time, and FIG. 9b is a graph showing that the phase change and the change in transmittance continue to be stably formed even when the heating (40°C) and cooling (20°C) cycles are repeated up to 1000 cycles.

[0140] The graphs illustrated in FIG. 9 represent the stability of reversible deformation of the liquid crystal elastomer proposed in the embodiment of the present invention, which means that the liquid crystal elastomer material according to the embodiment of the present invention behaves sufficiently stably and can be directly applied to a device.

[0141]

[0142] FIG. 10 is an image illustrating a process of selectively applying polydopamine (PDA) coating to some areas to simultaneously utilize patterning and physical motion in a liquid crystal elastomer according to one embodiment of the present invention, then patterning a QR code in one area and irradiating an IR lamp in another area to change the physical shape of the liquid crystal elastomer.

[0143] Figure 11 is an image illustrating an example of an application using a liquid crystal elastomer according to one embodiment of the present invention as a device. Figure 11 illustrates the potential use of a liquid crystal elastomer having the function of encrypting information through body temperature as a security device.

[0144] Figure 12 is an image illustrating another example of an application using a liquid crystal elastic body according to one embodiment of the present invention as a device. It demonstrates that a QR code containing a specific user's medical information is patterned using a writing process, and that the information can be easily encrypted and permanently deleted by attaching it to the body's skin. The red blocks represent areas that have been selectively deleted and reconstructed, and a new QR code is then formed to match the information of another user, allowing for its use.

[0145]

[0146] The above description is merely an illustrative example of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

Claims

1. A first region containing a liquid crystal; and A second region adjacent to the first region, including a liquid crystal, and including a phase different from that of the first region; Phase-patterned liquid crystal elastomer.

2. In paragraph 1, The above first region comprises a nematic phase, The second region above includes an isotropic phase, Phase-patterned liquid crystal elastomer.

3. In paragraph 2, The first region above includes a polydomain, Phase-patterned liquid crystal elastomer.

4. In paragraph 3, The second region is capable of reversible change into a polydomain of nematic phase. Phase-patterned liquid crystal elastomer.

5. In paragraph 1, The above liquid crystal elastomer comprises a guest molecule capable of dynamic crosslinking. Phase-patterned liquid crystal elastomer.

6. In paragraph 5, The above guest molecule is Containing at least one selected from the group consisting of RM257, EDDET, PETMP, and MBTA; Phase-patterned liquid crystal elastomer.

7. In paragraph 1, The second region has a width of 0.1 μm to 20 μm and is patterned by laser irradiation. Phase-patterned liquid crystal elastomer.

8. In paragraph 1, The first and second areas have different transparency values. Phase-patterned liquid crystal elastomer.

9. In paragraph 1, The boundary between the first and second areas is defined by a directional line. Phase-patterned liquid crystal elastomer.

10. In paragraph 1, The distinction between the first and second areas can disappear depending on external stimuli, and then another boundary can be formed, allowing for another distinction between the first and second areas. Phase-patterned liquid crystal elastomer.

11. In paragraph 1, Further comprising a third region including a phase different from the first region and the second region; The third region has a different phase from the first region and the second region among regions having a polydomain, monodomain, and isotropic phase. Phase-patterned liquid crystal elastomer.

12. A liquid crystal elastic body capable of generating a pattern by distinguishing multiple regions with different phases, Each of the above multiple regions can reversibly change transparency in response to external stimuli, The liquid crystal elastic body comprises the liquid crystal elastic body of claim 1. A device comprising a liquid crystal elastomer.

13. In paragraph 12, The above device is equipped with an information recognition security pattern, A device comprising a liquid crystal elastomer.

14. In paragraph 12, The above device is at least one of a wearable device, a security device, and a soft robot, It is possible to change the above pattern through human body temperature. A device comprising a liquid crystal elastomer.

15. In paragraph 12, The above device is capable of deleting and regenerating the pattern. A device comprising a liquid crystal elastomer.

16. Step for preparing a liquid crystal elastic body; A step of irradiating a laser onto a portion of the liquid crystal elastic body; and A step of cooling the liquid crystal elastic body irradiated with the laser; The above liquid crystal elastic body is the liquid crystal elastic body of claim 1. A method for manufacturing a phase-patterned liquid crystal elastomer.

17. In paragraph 16, further comprising a step of heating the liquid crystal elastic body to a predetermined temperature; A method for manufacturing a phase-patterned liquid crystal elastomer.

18. In paragraph 16, The step of preparing the above liquid crystal elastic body is: RM257, 1,4-bis(4-(3-acryloyloxypropoxy)benzoyloxy)-2-methylbenzene; EDDET, 2,2′-(ethylenedioxy)diethanethiol; PETMP and pentaerythritol tetrakis(3-mercaptopropionate); MBTA, comprising synthesizing a liquid crystal elastomer by introducing at least one selected from the group consisting of A step of irradiating a laser onto a portion of the above liquid crystal elastic body; Including that the phase of the laser-irradiated area changes as at least a portion of the liquid crystal elastic body is heated to a temperature of 30°C to 100°C. A method for manufacturing a phase-patterned liquid crystal elastomer.

19. In paragraph 16, A step of applying a physical external force that pulls the liquid crystal elastomer in at least one direction to deform a portion of the liquid crystal elastomer to elongate it; further comprising; A method for manufacturing a phase-patterned liquid crystal elastomer.

20. In paragraph 16, A step of irradiating a laser again on a portion of the liquid crystal elastic body on which the patterning is formed to erase the previously generated pattern, and irradiating a laser again on a specific portion; further comprising; A method for manufacturing a phase-patterned liquid crystal elastomer.

Images