A defogging liquid crystal dimming film and its preparation method

Abstract

The present invention relates to a demisting liquid crystal dimming film, comprising a main body including a dimming film and a demisting film disposed above the dimming film. The demisting film comprises a heated demisting layer and a first PET layer disposed in sequence. The demisting film comprises a first ITO metal layer, a liquid crystal polymer layer, a second ITO metal layer, and a second PET layer disposed in sequence. A first ITO conductive electrode is connected between the first ITO metal layer and the first PET layer, a second ITO conductive electrode is disposed between the second ITO metal layer and the second PET layer, the first ITO conductive electrode is connected to the first ITO metal layer, and the second ITO conductive electrode is connected to the second ITO metal layer. Two demisting electrodes are connected to the upper surface of the heated demisting layer. The heated demisting layer is a high-temperature metal film sputtered onto the first PET layer using a tungsten-titanium target. This overcomes the existing problems of poor aging resistance, high electrical resistance, high power consumption, and cracking of the metal layer caused by thermal expansion of common conductive materials.

Description

Technical Field

[0001] The invention relates to the technical field of optical heating devices, in particular to a defogging liquid crystal dimming film and a preparation method thereof. Background Art

[0002] Existing liquid crystal dimming films are manufactured by adding a layer of polymer and STN liquid crystal composite material between two ITO conductive films. Due to the birefringence of liquid crystal, the liquid crystal molecules form a regular arrangement when an electric field is applied, but become chaotically dispersed when the electric field is removed. Existing dimming films are opaque when powered off and transparent when powered on. Liquid crystal dimming films are manufactured using this multi-layer composite process, becoming transparent when powered on and frosted when powered off. Much of the construction industry requires daylighting, and traditional liquid crystal dimming films require a lamination process before installation, or they must be applied to the inside of glass. This method of application can cause the window glass to fog due to the temperature difference between indoors and outdoors, affecting both daylighting and visual quality.

[0003] The types of heating films are generally divided into transfer ink type, carbon fiber type, metal wire sheet type, and polymer conductive material type. Among them, the heating materials of transfer ink type electric heating films are generally graphite, metal powder, and metal oxides, and their disadvantage is that the thermal conductivity efficiency is average. The heating material of carbon fiber type electric heating films is generally carbon fiber, which begins to oxidize and lose weight in the air at 350°C, resulting in a change in resistivity, unstable electric heating performance, and even danger. The heating material of metal-based electric heating films is pure metal or metal alloy material, mainly copper, nickel, copper-nickel, iron-chromium-aluminum, which is prone to high electromagnetic radiation, easy to age, high energy consumption, and small heating area. The heating material of polymer conductive material type electric heating films is mainly conductive polymers, which have low thermal conductivity efficiency. The above traditional materials have poor comprehensive performance when preparing heating films with high thermal conductivity efficiency and high transparency. Summary of the Invention

[0004] In order to overcome at least some of the defects in the prior art, the present invention provides a defogging liquid crystal dimming film and a preparation method thereof, in order to improve the comprehensive heating performance and service life of the defogging heating film by utilizing new materials.

[0005] An embodiment of the present invention provides a demisting liquid crystal dimming film, comprising a body, the body comprising a dimming film and a demisting film disposed above the dimming film, the demisting film comprising a heated demisting layer and a first PET layer disposed in sequence, the demisting film comprising a first ITO metal layer, a liquid crystal polymer layer, a second ITO metal layer, and a second PET layer disposed in sequence;

[0006] A first ITO conductive electrode is connected between the first ITO metal layer and the first PET layer, a second ITO conductive electrode is provided between the second ITO metal layer and the second PET layer, the first ITO conductive electrode is connected to the first ITO metal layer, the second ITO conductive electrode is connected to the second ITO metal layer, and two defogging electrodes are connected to the upper surface of the heating defogging layer;

[0007] The heating defogging layer is a high-temperature metal film sputtered on the first PET layer by a tungsten-titanium target.

[0008] Furthermore, the thickness of the heated demisting layer is 0.05 μm-0.125 μm.

[0009] Furthermore, the thickness of the heated demisting layer is 0.108 μm.

[0010] Furthermore, the two demisting electrodes are axially symmetrically arranged along the central axis of the heating demisting layer, and the demisting electrodes are electrically connected to the heating demisting layer.

[0011] Furthermore, it also includes edge sealing glue coated on the outside of the body.

[0012] Furthermore, the demisting electrode is connected to a dimming power supply.

[0013] The present invention relates to a method for preparing a defogging liquid crystal dimming film, comprising the following steps:

[0014] Preparation of a defogging film: providing a first PET layer, and sputtering a tungsten-titanium target to form a high-temperature metal film on the first PET layer;

[0015] preparing a dimming film;

[0016] The defogging film is connected to the dimming film by heat pressing, and then cut to a specified angle according to actual needs to form a body;

[0017] Use edge sealing glue to seal the body around the perimeter and connect the flexible FPC for power-on testing;

[0018] After passing the test, the defogger liquid crystal dimming film is obtained.

[0019] Furthermore, preparing the dimming film includes the following steps:

[0020] providing a first ITO metal layer and a second ITO metal layer;

[0021] Evenly spraying liquid crystal polymer on the first ITO metal layer;

[0022] Compounding the first ITO metal layer sprayed with liquid crystal polymer and the second ITO metal layer;

[0023] Processing a first ITO conductive electrode on the first ITO metal layer;

[0024] processing a second ITO conductive electrode on the second ITO metal layer;

[0025] A second PET layer is provided, and a second ITO metal layer is compounded on the second PET layer, and then UV curing is performed to obtain a dimming film.

[0026] Furthermore, when the defogging film is hot-pressed onto the dimming film, the hot-pressing environment temperature is 120° C.-150° C., and the hot-pressing pressure is 8 MPa-12 MPa.

[0027] Furthermore, when the demisting film is hot-pressed onto the dimming film, a traction roller is used for traction. The size of the traction roller is 6 inches, and the rotation speed of the traction roller is 0.8-4 r / min.

[0028] The benefits of the present invention are as follows: since tungsten has properties such as a high melting point, high strength and a low thermal expansion coefficient, the tungsten-titanium alloy has a low resistivity, good thermal stability and oxidation resistance, so that the defogging liquid crystal dimming film formed by the processing can be used for a long time at conditions below 120°C, occupies a small space, is light in weight, is thin in thickness, and has high bending resistance; it can overcome the problems of poor aging resistance, high resistance, high power consumption, and cracking of the metal layer caused by thermal expansion of ordinary conductive materials in the prior art; the number of power-on cycles can reach 300,000 times, and the service life is greatly improved compared with the prior art, thereby reducing the cost of use; it can make other areas outside the electrode transparent to ensure the light transmission effect.

[0029] In order to make the above and other objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 It is a structural schematic diagram of the demisting heating film in the present invention. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] Reference Figure 1 A defogging liquid crystal dimming film in a preferred embodiment of the present invention includes a body 1, the body 1 including a dimming film 11 and a defogging film 12 disposed above the dimming film, the defogging film 12 including a heated defogging layer 121 and a first PET layer 122 disposed in sequence, and the dimming film 11 including a first ITO metal layer 111, a liquid crystal polymer layer 112, a second ITO metal layer 113, and a second PET layer 114 disposed in sequence;

[0034] A first ITO conductive electrode 3 is connected between the first ITO metal layer 111 and the first PET layer 122, a second ITO conductive electrode 4 is arranged between the second ITO metal layer 113 and the second PET layer 114, the first ITO conductive electrode 3 is connected to the first ITO metal layer 133, and the second ITO conductive electrode 4 is connected to the second ITO metal layer 113. Two demisting electrodes 5 are connected to the upper surface of the heated demisting layer; the heated demisting layer is a high-temperature metal film sputtered on the first PET layer 122 by a tungsten-titanium target.

[0035] In the above embodiment, the thickness of the heated demisting layer 121 is 0.05 μm-0.125 μm. In actual implementation, to ensure the rigidity and conductivity of the heated demisting layer 121, the processing thickness of the heated demisting layer 121 is 0.108 μm. Chen, of course, in other embodiments, the thickness of the heated demisting layer 121 can also be set to 0.05 μm, 0.08 μm, 0.1 μm, 0.12 μm, etc.

[0036] In the above embodiment, the two demisting electrodes 5 are axially symmetrically arranged along the central axis of the heated demisting layer 121, and the demisting electrodes 5 are electrically connected to the heated demisting layer 121. It also includes an edge-sealing glue 2 coated on the outside of the main body. The demisting electrodes are connected to a dimming power supply (not shown). In actual implementation, the dimming power supply adopts a multi-stage variable frequency power supply, which can be combined with a temperature sensor to adjust the voltage applied to the demisting electrode 5, thereby avoiding prolonged heating of the demisting liquid crystal dimming film, reducing the aging rate, and increasing its service life.

[0037] The present invention relates to a method for preparing a defogging liquid crystal dimming film, comprising the following steps:

[0038] Preparation of the defogging film 12: providing a first PET layer 122, and sputtering a tungsten-titanium target to form a high-temperature metal film on the first PET layer 122;

[0039] Prepare a dimming film 11;

[0040] The defogging film 12 is connected to the dimming film 11 by hot pressing, and then cut to a specified angle according to actual needs to form the main body 1;

[0041] Use edge sealing glue 2 to seal around the body and connect the flexible FPC for power-on test;

[0042] After passing the test, the defogger liquid crystal dimming film is obtained.

[0043] In the above embodiment, the preparation of the dimming film includes the following steps: providing a first ITO metal layer 111 and a second ITO metal layer 113; uniformly spraying a liquid crystal polymer on the first ITO metal layer 111; compounding the first ITO metal layer 111 sprayed with the liquid crystal polymer and the second ITO metal layer 113, and the compounding method can be glue coating combined with cold pressing or hot pressing; processing the first ITO conductive electrode 3 on the first ITO metal layer 111, and processing the second ITO conductive electrode 4 on the second ITO metal layer 113; providing a second PET layer 114, and compounding the second ITO metal layer 113 on the second PET layer 114, and forming by UV curing to obtain the dimming film.

[0044] In the above embodiment, when the demisting film 12 is hot-pressed onto the dimming film 11, the hot-pressing ambient temperature is 120°C-150°C. In actual implementation, the hot-pressing temperature is 130°C. The specific temperature is adjusted according to the thickness of the heated demisting layer. If the heated demisting layer 121 is thin, a lower hot-pressing temperature, such as 120°C, is used; if the heated demisting layer 121 is thick, a higher hot-pressing temperature, such as 150°C, is used. The hot-pressing pressure is 8-12 MPa. In actual implementation, the hot-pressing pressure is 10 MPa. The specific pressure is adjusted according to the thickness of the heated demisting layer 121. If the heated demisting layer 121 is thin, a lower hot-pressing pressure, such as 8 MPa, is used; if the heated demisting layer 121 is thick, a higher hot-pressing pressure, such as 12 MPa, is used. When the demisting film 12 is hot-pressed onto the dimming film 11 , a traction roller is used for traction. The size of the traction roller is 6 inches, and the rotation speed of the traction roller is 0.8-4 r / min.

[0045] Because tungsten has properties such as high melting point, high strength and low thermal expansion coefficient, tungsten-titanium alloy has low resistivity, good thermal stability and antioxidant properties, so that the defogger liquid crystal dimming film formed by the process can be used for a long time under conditions below 120°C, occupies a small space, is light in weight, thin in thickness, and has high bending resistance; it can overcome the problems of poor aging resistance, high resistance, high power consumption, and cracking of the metal layer caused by thermal expansion of ordinary conductive materials in the existing technology; the number of power-on cycles can reach 300,000 times, and the service life is greatly improved compared with the existing technology, thereby reducing the cost of use; it can make other areas outside the electrode transparent to ensure the light transmission effect.

[0046] In order to further demonstrate the comprehensive performance of the defogger liquid crystal dimming film in this application, defogger liquid crystal dimming film, nano-silver coated liquid crystal film, metal grid heating layer liquid crystal film, graphene heating layer liquid crystal film and carbon nanotube liquid crystal film of the same size were cut into three groups for basic testing. The first group was then placed in a -40℃-120℃ environment and operated continuously for 96 hours, and the time it took to heat up from 0℃ to 60℃ was tested. The second group was placed at 120℃ and operated continuously for 96 hours, and the time it took to heat up from 0℃ to 60℃ was tested. The third group was subjected to power-on and power-off cycles, and the time it took to heat up from 0℃ to 60℃ was tested when the number of cycles was 100, 3000 and 30,000 respectively. The test results are listed below.

[0047] Note: The test samples are all 200mm*500mm samples, the test power supply voltage is AC36V, and the output full load power is 500W. In a pure resistance circuit, according to Ohm's law U=IR, substituting it into P=UI, we can also get: P=I2R=(U2) / R. The central symmetrical point between the two end points of the test electrode is the test point of this experiment.

[0048]

[0049] Table 1 Basic test table

[0050]

[0051] Table 2 Power-on test table

[0052] It can be seen from the above table that the demisting liquid crystal dimming film processed by the present invention can still work for a long time under the condition of temperature changes, can greatly slow down the aging, and ensure that the demisting liquid crystal dimming film can heat up normally; when the number of cycles reaches 30,000 times, it can still be heated normally. Compared with the existing technology, it can significantly reduce the aging speed and greatly improve the service life.

[0053] Specific embodiments are used in the present invention to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A defogging liquid crystal dimming film, comprising a body and an edge-sealing adhesive coated on the outside of the body; the body comprising a first PET layer, a first ITO metal layer, a liquid crystal polymer layer, a second ITO metal layer, and a second PET layer arranged in sequence; a first ITO conductive electrode is connected between the first ITO metal layer and the first PET layer, a second ITO conductive electrode is provided between the second ITO metal layer and the second PET layer, the first ITO conductive electrode is connected to the first ITO metal layer, and the second ITO conductive electrode is connected to the second ITO metal layer. Its characteristics are: The main body also includes a high-temperature metal film with a thickness of 0.08μm-0.12μm sputtered on the first PET layer by a tungsten-titanium target; two demisting electrodes are electrically connected to the upper surface of the high-temperature metal film, and the two demisting electrodes are axially symmetrically arranged along the central axis of the high-temperature metal film; the demisting electrodes are connected to a dimming power supply.

2. The defogging liquid crystal dimming film according to claim 1, characterized in that: The thickness of the high-temperature metal film is 0.108 μm.

3. The method for preparing the defogging liquid crystal dimming film according to any one of claims 1 to 2, characterized in that: The following steps are involved: Preparation of a defogging film: providing a first PET layer, and sputtering a tungsten-titanium target to form a high-temperature metal film on the first PET layer; preparing a dimming film; The defogging film is connected to the dimming film by heat pressing, and then cut to a specified angle according to actual needs to form a body; Use edge sealing glue to seal the body around the perimeter and connect the flexible FPC for power-on testing; After passing the test, the defogger liquid crystal dimming film is obtained.

4. The method for preparing the defogging liquid crystal dimming film according to claim 3, wherein: providing a first ITO metal layer and a second ITO metal layer; Evenly spraying liquid crystal polymer on the first ITO metal layer; Compounding the first ITO metal layer sprayed with liquid crystal polymer and the second ITO metal layer; Processing a first ITO conductive electrode on the first ITO metal layer; processing a second ITO conductive electrode on the second ITO metal layer; A second PET layer is provided, and a second ITO metal layer is compounded on the second PET layer, and then UV curing is performed to obtain a dimming film.

5. The method for preparing the defogging liquid crystal dimming film according to claim 4, characterized in that: When the defogging film is hot-pressed onto the dimming film, the hot-pressing environment temperature is 120° C.-150° C., and the hot-pressing pressure is 8 MPa-12 MPa.

6. The method for preparing the defogging liquid crystal dimming film according to claim 5, characterized in that: When the demisting film is hot-pressed onto the dimming film, a traction roller is used for traction. The size of the traction roller is 6 inches, and the rotation speed of the traction roller is 0.8-4 r / min.

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