CN108977205B - Special liquid crystal composition for handwriting board and flexible handwriting film based on special liquid crystal composition - Google Patents
Special liquid crystal composition for handwriting board and flexible handwriting film based on special liquid crystal composition Download PDFInfo
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- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
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Abstract
The invention discloses a liquid crystal composition special for a handwriting board and a flexible handwriting film based on the same, which are characterized in that: uniformly mixing nematic liquid crystal, chiral dopant, hyperbranched resin, photoinitiator, light stabilizer and UV monomer to obtain a liquid crystal composition; the liquid crystal composition is uniformly coated between two layers of nano silver wire transparent conductive films, and then the flexible handwriting film is prepared through UV curing. The handwriting film prepared by the invention comprises the following components: due to the use of the hyperbranched resin, the handwriting film has high brightness, fast reaction and excellent sensitivity; due to the use of the photoinitiator and the light stabilizer with excellent yellowing resistance, the durability of the handwriting film is improved; the use of the low-sheet resistance nano silver wire transparent conductive film makes the film more suitable for preparing large-size and flexible handwriting films; in addition, the handwriting film has a simple structure and is easy to realize industrial production.
Description
Technical Field
The invention relates to the field of liquid crystal display, in particular to the technical field of handwriting boards, and more particularly relates to a liquid crystal composition special for a handwriting board and a flexible handwriting film based on the same.
Background
Along with the development of times and social progress, the application requirements of the liquid crystal handwriting board in the aspects of education and teaching, meetings, drawing, design and the like are continuously increased, for example, the liquid crystal handwriting board is used for replacing a traditional blackboard to solve the dust problem of chalk, meanwhile, paperless teaching can be realized, energy is not needed when the display content is kept, and the energy consumption is extremely low. Due to the increasing demand and application range of handwriting boards, the requirements for handwriting boards are gradually increasing, for example: when the LED display screen is used in a conference or a classroom, the space is large, remote observation is needed, and the LED display screen is required to have a large size, high display brightness and high definition. When it is used in design or other auxiliary fields, it is required to have a fast response, high sensitivity and good durability.
The handwriting board is generally assembled by a handwriting film, a light absorption film (black film), a plastic shell, a booster circuit and an erasing circuit, wherein the handwriting film is a main functional component. The handwriting film is of a three-layer structure, the upper layer and the lower layer are base films with conductive electrode layers, and the middle layer is bistable cholesteric liquid crystal. The liquid crystal handwriting boards sold in the market at present are all prepared on the basis of ITO conductive films, and when the liquid crystal handwriting boards are used on large-size handwriting boards, the liquid crystal handwriting boards are poor in flexibility and general in erasing sensitivity, and large-size production and preparation are not facilitated.
Patent CN107236551 proposes a liquid crystal composition and a liquid crystal writing film prepared therefrom, wherein a large amount of UV monomers are used in the liquid crystal composition, and although the UV monomers have longer carbon chains, the UV monomers still have certain rigidity after curing, which cannot achieve higher flexibility, and influence the degree of freedom of liquid crystal molecules, thereby reducing the display brightness. Meanwhile, ITO is brittle and has high sheet resistance, and flexible display and large size cannot be realized.
Therefore, at present, a flexible handwriting film special for a handwriting board, which has the advantages of good flexibility, high brightness, fast reaction, high sensitivity, excellent durability, suitability for various models such as large, medium and small sizes and the like and can be completely industrially produced, is urgently needed to be prepared.
Disclosure of Invention
In order to avoid the defects of the prior art, the invention provides a special liquid crystal composition for a handwriting board and a flexible handwriting film based on the special liquid crystal composition, and aims to obtain the special flexible handwriting film for the handwriting board, which has high brightness, quick response, high sensitivity and excellent durability, is suitable for all sizes of large, medium and small and can realize industrial production.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention firstly discloses a special liquid crystal composition for a handwriting board, which comprises the following components in percentage by mass:
preferably, the nematic liquid crystal is nematic liquid crystal C70/02CN or nematic liquid crystal nCB (4-n-alkyl.4' -cyanobiphenols, n is 5-8); the chiral dopant is S811, R1011, R5011, CB15 or CNL-617L.
Preferably, the hyperbranched resin has a viscosity of less than 10000mPa & s (25 ℃), a functionality of more than 6 and a curing time of less than 5s, and can be selected from: HD-2280 (Thick tripod chemical industry), HP6919, HP9710 (Haohui new material), DM588 (double bond chemical industry), CN9013NS, CN8885NS (Saedoma), WDS-9700, WDS-9500 (Viduss), UV7-4XT (Zhongshan Qianye), SeHBP-UV208 (Western Bao biology), INV-UV985 (Haoyi chemical industry), RU-907C, RU-9075B (Recheng resin), RUA-050 (Japanese Asia).
Preferably, the photoinitiator is one of Irgacure127 (basf), Irgacure754 (basf), STU1105 (new petty material) and ESACURE KIP150 (ningbodi) which have excellent yellowing resistance. The photoinitiator used in patent CN107236551 is only suitable for ITO substrate, and has poor yellowing resistance when used on the conductive film substrate of the present invention, resulting in poor stability of the prepared handwriting board.
Preferably, the light stabilizer is one of Tinuvin5151 (Pasvu), Tinuvin 326 (Pasvu), V703 (Aidicke), UV-3808PP5, UV-2908 (cyante), BW-10LD (Qingdada chemical industry), Eversorb 74 and EVERSORB80 (Taiwan photochemical);
preferably, the UV monomer is low-viscosity, good-dilutability and non-yellowing monofunctional resin trimethylolpropane formal acrylate.
The invention further discloses a preparation method of the special liquid crystal composition for the handwriting board, which is characterized by comprising the following steps: firstly, adding hyperbranched resin and UV monomers into a dispersion cylinder, and mechanically stirring for 30min through a tetrafluoroethylene stirring rod at the speed of 1000 r/min; and then adjusting the stirring speed to 500r/min, gradually adding nematic liquid crystal, continuing to stir for 30min, finally sequentially adding the chiral dopant, the photoinitiator and the light stabilizer, and continuing to stir for 30min to obtain the special liquid crystal composition for the handwriting board.
The invention also discloses a flexible handwriting film which is of a three-layer structure and comprises a first electrode layer, a liquid crystal layer and a second electrode layer from top to bottom in sequence; the liquid crystal layer is formed by uniformly coating the liquid crystal composition between the first electrode layer and the second electrode layer and then carrying out UV curing. The outer surface of the upper electrode is a writing surface.
Preferably, the first electrode layer and the second electrode layer adopt a nano silver wire transparent conductive film; the nano silver wire transparent conductive film is formed by coating nano silver wire conductive ink on a flexible transparent base film. The silver nanowire conducting layers of the two electrode layers are opposite to each other and fixed with the liquid crystal layer positioned between the silver nanowire conducting layers.
Preferably, the flexible transparent base film is a PET film with the thickness of 50-125 μm, and the sheet resistance of the nano silver wire conducting layer is 10-40 omega/□.
Compared with the prior art, the invention has the following beneficial effects:
1. the special liquid crystal composition for the handwriting board is diluted by using only a small amount of non-yellowing monomer with single functional group, and is cured and crosslinked by using hyperbranched resin, wherein the hyperbranched resin has the characteristics of low viscosity, good fluidity, good solubility, high end-capping functionality, high reaction activity and the like, and meanwhile, the hyperbranched resin has no in-chain winding property and is in an amorphous soft state in a common state, and liquid crystal is more uniformly distributed in the hyperbranched resin and has high degree of freedom; the light-emitting diode can be smoothly rotated to a plane texture state in the writing and pressing process and is matched with a chiral agent, so that light rays with specific wavelengths are reflected, the display brightness is higher, the contrast is excellent, the reaction is fast, and the writing sensitivity is high;
2. the photoinitiator used in the invention has excellent anti-yellowing effect, and a small amount of light stabilizer is added to ensure that the prepared handwriting film has more excellent durability;
3. the invention uses the nano silver wire transparent conductive film to replace a common ITO film, has good flexibility and low sheet resistance, is more suitable for preparing large-size flexible handwriting films, and has better writing effect.
Drawings
FIG. 1 is a schematic structural diagram of a flexible handwriting film of the invention;
reference numbers in the figures: 1 is a flexible transparent basal membrane, 2 is a nano silver wire conducting layer, and 3 is a liquid crystal layer.
Detailed Description
The present invention will be described in detail with reference to the following examples, which are carried out on the premise of the technical solution of the present invention, and give detailed embodiments and specific procedures, but the scope of the present invention is not limited to the following examples.
The silver nanowire transparent conductive film used in the following examples was a silver nanowire conductive layer formed by coating silver nanowire conductive ink on a 125 μm thick PET film, and the sheet resistance of the silver nanowire conductive layer was 25 Ω/□, which was selected from WJF25 of co-fertilizer microcrystalline material science and technology ltd, and was commercially available.
Example 1
(1) Preparation of a liquid crystal composition: adding 30g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, the stirring speed is adjusted to be 500r/min, 53.7g of nematic liquid crystal C70/02CN is gradually added, and the stirring is continued for 30 min; finally, 8g of chiral dopant R1011, 0.9g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 2
(1) Preparation of a liquid crystal composition: 40g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate were added to a dispersion cylinder and stirred for 30min using a tetrafluoroethylene stirring rod 1000 r/min. Then adjusting the stirring speed to 500R/min, gradually adding 43.4g of nematic liquid crystal C70/02CN, continuing to stir for 30min, finally sequentially adding 8g of chiral dopant R1011, 1.2g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151, and continuing to stir for 30min to prepare the liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 3
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then adjusting the stirring speed to 500R/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, continuously stirring for 30min, finally sequentially adding 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151, and continuously stirring for 30min to obtain the liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 4
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin CN8885NS and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then adjusting the stirring speed to 500R/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, continuously stirring for 30min, finally sequentially adding 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151, and continuously stirring for 30min to obtain the liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 5
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin INV-UV985 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then adjusting the stirring speed to 500R/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, continuously stirring for 30min, finally sequentially adding 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151, and continuously stirring for 30min to obtain the liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Comparative example 1
(1) Preparation of a liquid crystal composition: adding 50g of six-functional monomer DPHA and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then adjusting the stirring speed to 500R/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, continuously stirring for 30min, finally sequentially adding 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151, and continuously stirring for 30min to obtain the liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Table 1: formulation and Performance comparison of examples 1-5 with comparative example 1
From the comparison results of examples 1-5 and comparative example 1, it can be seen that the performance of the tablet can be effectively improved by using hyperbranched resin to replace polyfunctional monomer for crosslinking and curing in the liquid crystal composition, because the crosslinking network is too dense, the rigidity is strong, the flexibility is poor, the liquid crystal is completely fixed in the resin crosslinking network, the liquid crystal cannot smoothly rotate to a planar texture state (P state) during writing, and the liquid crystal is unevenly distributed in the liquid crystal due to the winding property of the highly functional monomer, the display effect and the durability are very poor; from examples 1 to 3, it can be seen that, as the content of the hyperbranched resin in the liquid crystal composition increases, the uniformity of the liquid crystal in the liquid crystal composition increases, the P-state conversion rate of the liquid crystal becomes high when the liquid crystal is pressed during writing, and the display effect becomes more excellent, because the hyperbranched resin has the characteristics of low viscosity, good fluidity, good solubility, high end-capping functionality, high reactivity, and the like, and meanwhile, the hyperbranched resin has no in-chain winding property, is an amorphous soft state in a normal state, and the liquid crystal is uniformly distributed in the hyperbranched resin, and can smoothly rotate to P during the pressing process of writing, so that light with a specific wavelength is reflected, the display brightness is higher, the contrast is excellent, and the reaction is fast and the writing sensitivity is; from examples 3 to 5, it is clear that the use of different hyperbranched resins in the liquid crystal composition can achieve better display effects and other properties.
Example 6
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure754 and 0.4g of light stabilizer Tinuvin5151 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 7
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator ESACURE KIP150 and 0.4g of light stabilizer Tinuvin5151 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 8
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer UV-2908 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, carrying out UV curing, and rolling to obtain the flexible handwriting film. (2) Uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Example 9
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Eversorb 74 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Comparative example 2
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011 and 1.5g of photoinitiator Irgacure127 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Comparative example 3
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator 907 and 0.4g of light stabilizer Tinuvin5151 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two layers of nano silver wire transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the flexible handwriting film.
Table 2: formulation and Performance comparison of examples 3, 6-9 with comparative examples 2-3
As can be seen from comparison of example 3 with examples 6 to 7 and comparative example 3, the use of different photoinitiators with excellent yellowing resistance can improve the light resistance stability (ultraviolet absorber resistance and xenon lamp resistance) of the handwriting pad, thereby improving the service life of the handwriting pad, especially the outdoor service life; it is also clear from examples 3 and 8-9 and comparative example 2 that the use of light stabilizers is effective in improving the light-resistant stability of the writing pad, thereby improving the service life of the writing pad.
Comparative example 4
(1) Preparation of a liquid crystal composition: adding 50g of hyperbranched resin HP6919 and 7gUV monomer trimethylolpropane formal acrylate into a dispersion cylinder, and stirring for 30min by using a tetrafluoroethylene stirring rod at 1000 r/min; then, adjusting the stirring speed to 500r/min, gradually adding 33.1g of nematic liquid crystal C70/02CN, and continuing stirring for 30 min; finally, 8g of chiral dopant R1011, 1.5g of photoinitiator Irgacure127 and 0.4g of light stabilizer Tinuvin5151 are sequentially added, and the mixture is continuously stirred for 30min to prepare a liquid crystal composition;
(2) uniformly coating the liquid crystal composition prepared in the step (1) between two ITO transparent conductive films, and carrying out UV curing (500 mJ/cm)2And 3s), rolling to obtain the handwriting film.
Table 3: example 3 comparative example 4 method and Performance comparison
As can be seen from example 3 and comparative example 4, the handwriting film for a handwriting board, which was manufactured using silver nanowires instead of ITO, was more excellent in flexibility. Meanwhile, under the condition of the same optical performance, the sheet resistance of the nano silver wire transparent conductive film is lower, the driving voltage required during erasing is relatively lower, and the electricity is saved.
The present invention is not limited to the above exemplary embodiments, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (4)
1. A liquid crystal composition special for a writing pad is characterized in that: the liquid crystal composition is used for a flexible handwriting film taking a nano silver wire transparent conductive film as an electrode layer; the liquid crystal composition comprises the following components in percentage by mass:
the nematic liquid crystal is nematic liquid crystal C70/02CN or nematic liquid crystal nCB, and n is 5-8;
the chiral dopant is S811, R1011, R5011, CB15 or CNL-617L;
the hyperbranched resin is one of HP6919, CN8885NS and INV-UV 985;
the photoinitiator is one of Irgacure127, Irgacure754, STU1105 and ESACURE KIP 150;
the light stabilizer is one of Tinuvin5151, Tinuvin 326, V703, UV-3808PP5, UV-2908, BW-10LD, Eversorb 74 and EVERSORB 80;
the UV monomer is single functional group resin trimethylolpropane formal acrylate.
2. A method for preparing the liquid crystal composition special for the writing pad of claim 1, which is characterized in that: firstly, adding hyperbranched resin and UV monomers into a dispersion cylinder, and mechanically stirring for 30min through a tetrafluoroethylene stirring rod at the speed of 1000 r/min; and then adjusting the stirring speed to 500r/min, gradually adding nematic liquid crystal, continuing to stir for 30min, finally sequentially adding the chiral dopant, the photoinitiator and the light stabilizer, and continuing to stir for 30min to obtain the special liquid crystal composition for the handwriting board.
3. A flexible writing film, comprising: the flexible handwriting film is of a three-layer structure and sequentially comprises a first electrode layer, a liquid crystal layer and a second electrode layer from top to bottom; the liquid crystal layer is formed by uniformly coating the liquid crystal composition of claim 1 between a first electrode layer and a second electrode layer and then carrying out UV curing;
the first electrode layer and the second electrode layer adopt nano silver wire transparent conductive films; the nano silver wire transparent conductive film is formed by coating nano silver wire conductive ink on a flexible transparent base film.
4. The flexible writing film of claim 3, wherein: the flexible transparent base film is a PET film with the thickness of 50-125 μm, and the sheet resistance of the nano silver wire conducting layer is 10-40 omega/□.
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| CN105062505B (en) * | 2015-07-15 | 2017-11-14 | 深圳市景世源科技有限公司 | Polymer liquid crystal composition, liquid crystal handwriting display device and preparation method |
| CN107236551A (en) * | 2017-05-16 | 2017-10-10 | 深圳市唯酷光电有限公司 | The hand-written film of liquid-crystal composition, liquid crystal and liquid crystal handwriting pad |
| CN107632437B (en) * | 2017-09-29 | 2019-02-26 | 深圳市艾尚写科技有限公司 | A kind of energy-saving liquid crystal display and liquid crystal handwriting device |
| CN108231246B (en) * | 2018-03-01 | 2020-01-03 | 合肥微晶材料科技有限公司 | Ultraviolet-resistant nano silver wire conductive film and manufacturing method thereof |
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2018
- 2018-08-14 CN CN201810919471.0A patent/CN108977205B/en active Active
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