Liquid crystal handwriting film manufacturing method and manufacturing equipment

Abstract

The present invention provides a method and equipment for manufacturing a liquid crystal handwriting film, and relates to the technical field of liquid crystal handwriting films. The method and equipment for manufacturing a liquid crystal handwriting film include S10: preparing at least two liquid crystal materials with different central reflection wavelengths; S20: pouring at least two liquid crystal materials with different central reflection wavelengths into the same position between a first substrate and a second substrate; S30: compounding the first substrate, the second substrate, and the liquid crystal material poured between the first substrate and the second substrate into a liquid crystal handwriting film. The equipment for manufacturing a liquid crystal handwriting film includes: a laminating device and a liquid crystal mixed material pouring device, and the liquid crystal material mixed pouring device is used to mix different types of liquid crystal materials and pour them into the same position of the liquid crystal handwriting film, or pour different types of liquid crystal materials into the same position of the liquid crystal handwriting film and then mix them. The method and equipment for manufacturing a liquid crystal handwriting film of the present invention can produce a liquid crystal handwriting film with richer colors and various color changes.

Description

Technical Field

[0001] The invention relates to the technical field of liquid crystal handwriting films, in particular to a method and equipment for manufacturing a liquid crystal handwriting film. Background Art

[0002] In the prior art, liquid crystal writing tablets are often manufactured by utilizing the characteristic of cholesteric bistable liquid crystals that they can maintain display without continuous power supply. Cholesteric liquid crystals have two stable states, FC state and P state. When the cholesteric liquid crystal is in the FC state, the liquid crystal writing tablet appears to be transparent from the outside; when the cholesteric liquid crystal is in the P state under pressure, it can reflect light of a fixed wavelength, so that the liquid crystal writing tablet can display handwriting. Since the FC state and the P state of the cholesteric liquid crystal do not require voltage and can be maintained for a long time, the energy consumption of this type of liquid crystal writing tablet is extremely low.

[0003] The existing method for manufacturing liquid crystal handwriting films is to use a liquid crystal perfusion device to mix cholesteric liquid crystal and glue and then perfuse them between a top substrate and a bottom substrate with a transparent electrode film, and then press the top substrate, the bottom substrate and the mixture of cholesteric liquid crystal and glue together to form a handwriting film. The current manufacturing method often perfuses liquid crystal materials that can reflect light of different wavelengths into different positions of the handwriting film, thereby achieving different colors in different areas of the same handwriting film. Although the liquid crystal handwriting board manufactured by the aforementioned method can display multiple colors in the same handwriting board, only a single color can be fixedly displayed in the same area of ​​the handwriting board, and different colors form obvious block divisions. The color changes are fixed and too single, and the colors that the handwriting board can present are also very limited. Summary of the invention

[0004] In view of this, the present invention provides a liquid crystal handwriting film manufacturing method and manufacturing equipment to solve the technical problem that the handwriting film manufactured by the existing liquid crystal handwriting film manufacturing technology can display insufficient colors and monotonous color changes.

[0005] In a first aspect, the present invention provides a method for manufacturing a liquid crystal handwriting film, comprising the following steps:

[0006] S10: preparing at least two liquid crystal materials with different central reflection wavelengths;

[0007] S20: injecting at least two liquid crystal materials with different central reflection wavelengths into the same position between the first substrate and the second substrate to obtain a mixed liquid crystal material mixed according to a predetermined mass percentage, wherein a first transparent electrode is provided on a surface of the first substrate facing the second substrate, and a second transparent electrode is provided on a surface of the second substrate facing the first substrate;

[0008] S30: Compounding the first substrate, the second substrate, and the mixed liquid crystal material between the first substrate and the second substrate into a liquid crystal handwriting film.

[0009] Preferably, the S20 further includes the following steps:

[0010] S211: firstly, mixing at least two liquid crystal materials with different central reflection wavelengths according to a predetermined mass percentage to obtain a mixed liquid crystal material;

[0011] S212: pouring the mixed liquid crystal material between the first substrate and the second substrate.

[0012] Preferably, the S20 comprises: moving the injection ports for injecting liquid crystal materials with different central reflection wavelengths to the same injection position for injection according to a predetermined time sequence.

[0013] Preferably, the liquid crystal material comprises cholesteric liquid crystal and an adhesive, and the cholesteric liquid crystal comprises nematic liquid crystal and a chiral agent for adjusting a central reflection wavelength of the cholesteric liquid crystal.

[0014] Preferably, the cholesteric phase liquid crystal includes a first cholesteric phase liquid crystal and a second cholesteric phase liquid crystal, the central reflection wavelength of the first cholesteric phase liquid crystal is λ1, the central reflection wavelength of the second cholesteric phase liquid crystal is λ2, and d=|λ1-λ2|, d≥80nm.

[0015] Preferably, in S212: when the mixed liquid crystal material is poured between the first substrate and the second substrate, the mass percentage of liquid crystal materials with different central reflection wavelengths in the mixed liquid crystal material poured between the first substrate and the second substrate varies randomly with the position of the liquid crystal handwriting film.

[0016] Preferably, in S211, the flow rate of at least one liquid crystal material with a central reflection wavelength is reduced from a first preset flow rate to a second preset flow rate.

[0017] Preferably, after S30, the method further includes S40: curing the mixed liquid crystal material located on the first substrate and the second substrate by using an external field to form a polymer dispersed liquid crystal.

[0018] In a second aspect, the present invention provides a liquid crystal handwriting film manufacturing device, comprising:

[0019] A liquid crystal material mixing and pouring device, the liquid crystal material mixing and pouring device is used to mix at least two different types of liquid crystal materials and then pour them into the same position of the liquid crystal handwriting film, or to pour at least two different types of liquid crystal materials into the same position of the liquid crystal handwriting film and then mix them;

[0020] A laminating device, the laminating device comprising a first pressing roller and a second pressing roller, the rotation axes of the first pressing roller and the second pressing roller are parallel, and the first pressing roller and the second pressing roller are spaced a preset distance apart to press the liquid crystal handwriting film;

[0021] The laminating device is used to control the first pressing roller and the second pressing roller to rotate in opposite directions to laminar the liquid crystal handwriting film after the liquid crystal material mixing and filling device has filled the liquid crystal material.

[0022] Preferably, the rotation speed of the first pressing roller and the second pressing roller is 0.25 m / min to 0.85 m / min.

[0023] Beneficial effects: The manufacturing method and manufacturing equipment of the liquid crystal handwriting film of the present invention first prepare a plurality of liquid crystal materials with different central reflection wavelengths, then mix the liquid crystal materials with different central reflection wavelengths and pour them into the same position between the first substrate and the second substrate, and finally compound the first substrate, the second substrate and the mixed liquid crystal material into a liquid crystal handwriting film. The same position of the handwriting film thus produced is mixed with liquid crystal materials of various colors. Different types of liquid crystal materials work together at the same position to display colors that a single liquid crystal material cannot display. When the proportions of various liquid crystal materials at different positions are different, the colors displayed are also different. Therefore, the liquid crystal handwriting film manufactured by the method and equipment of the present invention can display a variety of colorful colors. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings required for use in the embodiment of the present invention will be briefly introduced below. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work, and these are all within the protection scope of the present invention.

[0025] Figure 1 This is a flow chart of a method for manufacturing a liquid crystal handwriting film according to Embodiment 1 of the present invention;

[0026] Figure 2 This is a flow chart of a method for compositely forming a liquid crystal handwriting film in Example 2 of the present invention;

[0027] Figure 3 This is a flow chart of a method for manufacturing a liquid crystal handwriting film according to Embodiment 2 of the present invention;

[0028] Figure 4 It is a flow chart of a method for manufacturing a liquid crystal handwriting film including a curing process of a mixed liquid crystal material according to Embodiment 2 of the present invention;

[0029] Figure 5 It is a structural schematic diagram of the liquid crystal handwriting film manufacturing equipment of the present invention;

[0030] Figure 6 It is a structural schematic diagram of the liquid crystal material pouring device of the present invention;

[0031] Figure 7 It is a structural schematic diagram of a liquid crystal material pouring device with a valve according to the present invention;

[0032] Figure 8 It is a structural schematic diagram of a liquid crystal material pouring device with a first driving device according to the present invention;

[0033] Fig. 9 It is a structural schematic diagram of a liquid crystal handwriting film manufacturing device with a first driving device of the present invention;

[0034] Fig.10 It is a structural schematic diagram of the present invention that uses rotation to change the position of the liquid crystal material injection port;

[0035] Fig.11 It is a structural schematic diagram of a liquid crystal handwriting film manufacturing device with an ultraviolet light curing device of the present invention;

[0036] Fig.12 It is a structural schematic diagram of a liquid crystal handwriting film manufacturing device having a material unwinding device and a winding mechanism of the present invention;

[0037] Fig.13 It is a schematic structural diagram of the handwriting film of the present invention.

[0038] Parts and numbers in the figure: first conductive layer 1, second conductive layer 2, liquid crystal layer 3, transparent substrate layer 4, background substrate layer 5, lamination device 10, first pressing roller 11, second pressing roller 12, lamination gap 13, first substrate 21, second substrate 22, liquid crystal material filling device 30, conveying channel 31, mixing channel 32, liquid crystal material filling port 33, valve 34, first driving device 35, ultraviolet light curing device 40, first unloading device 50, second unloading device 60, winding mechanism 70. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described in conjunction with the drawings in the embodiment of the present invention. It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In the description of the present invention, it should be understood that the orientation or position relationship indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such a process, method, article or device. In the absence of further restrictions, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article or device comprising the elements. If there is no conflict, the various features in the embodiments and examples of the present invention can be combined with each other, all within the scope of protection of the present invention.

[0040] Liquid crystal handwriting tablets are usually composed of shell materials, control circuit boards, and handwriting films. The handwriting films are transparent films, the first layer of ITO transparent electrodes, liquid crystal layers, the first layer of ITO transparent electrodes, and black bottom films from top to bottom. The liquid crystal layer contains cholesteric liquid crystals made of nematic liquid crystals and chiral agents.

[0041] The handwriting film can be made by filling a mixed monomer or prepolymer that can be polymerized under an external field (such as light, heat, etc.), liquid crystal and related liquid crystal compositions (liquid crystal materials with chiral agents added) between two substrates with conductive layers, wherein the ingredients and ratio of the liquid crystal composition can adjust the wavelength band of light reflected by the cholesteric liquid crystal.

[0042] The cholesteric liquid crystal is flat and arranged in layers, with the molecules in the layers parallel to each other. When the cholesteric liquid crystal is in the focal conic texture state (FC state), the long axis of the cholesteric liquid crystal molecules is perpendicular to the layer plane, and the direction of the long axis of the molecules in different layers changes slightly; when the cholesteric liquid crystal is in the planar texture state (P state), the long axis of the molecules is parallel to the layer plane, and the direction of the long axis of the molecules in different layers changes slightly, and they will be arranged into a spiral structure along the normal direction of the layer. In the FC state, light directly passes through the liquid crystal layer and is absorbed by the black film at the bottom, and what is presented is a completely black state; when we press the liquid crystal film with our fingers or other harder objects, the liquid crystal is squeezed and flipped by pressure, and the flipped area is the P state. When natural light irradiates the flipped area of ​​the liquid crystal layer, light of a certain wavelength is reflected, and the rest of the colors are absorbed, forming handwriting of the corresponding color; when the clear key on the handwriting board is pressed, the control circuit energizes the membrane, and the flipped area is stimulated by voltage to return to the FC state. The FC state and the P state are the aforementioned bistable states, and the mutual conversion between the FC state and the P state can be achieved by driving voltage.

[0043] Since different chiral agents and nematic phase liquid crystals can be mixed to prepare cholesteric phase liquid crystals that reflect light of different wavelengths, the prior art injects cholesteric phase liquid crystals prepared by different chiral agents into different areas of the same handwriting board, so that each area divided by the handwriting board can display different colors. The liquid crystal handwriting film manufacturing method of the present application first mixes a plurality of liquid crystal materials of different colors together and then injects them between two layers of substrates through a liquid crystal material injection port, thereby producing a liquid crystal handwriting film that can display rich colors. The liquid crystal materials of different colors herein refer to liquid crystal materials that can reflect light of different colors after being made into a liquid crystal handwriting film. The liquid crystal material is composed of cholesteric phase liquid crystals that can reflect light of a specific wavelength band and an adhesive. The color displayed after the liquid crystal material is made into a liquid crystal handwriting film is determined by the wavelength band of the light reflected by the liquid crystal material.

[0044] Embodiment 1:

[0045] like Figure 1 As shown, this embodiment provides a method for manufacturing a liquid crystal handwriting film, comprising the following steps:

[0046] S10: preparing at least two liquid crystal materials with different central reflection wavelengths;

[0047] S20: injecting at least two liquid crystal materials with different central reflection wavelengths into the same position between the first substrate and the second substrate to obtain a mixed liquid crystal material mixed according to a predetermined mass percentage, wherein a first transparent electrode is provided on a surface of the first substrate facing the second substrate, and a second transparent electrode is provided on a surface of the second substrate facing the first substrate;

[0048] S30: Compounding the first substrate, the second substrate 22 and the mixed liquid crystal material injected between the first substrate and the second substrate into a liquid crystal handwriting film.

[0049] The liquid crystal material described in S10 is obtained by mixing a cholesteric phase liquid crystal and an adhesive, and the cholesteric phase liquid crystal is mixed with a nematic phase liquid crystal and a chiral agent for adjusting the central reflection wavelength of the cholesteric phase liquid crystal. The pitch of the cholesteric phase liquid crystal can be adjusted by controlling the type and content of the chiral agent, so as to prepare cholesteric phase liquid crystals with various central reflection wavelengths. The types of the aforementioned chiral agents are divided based on the HTP value of the chiral agent, and different types of chiral agents refer to chiral agents with different HTP values. HTP is the twisting force constant of the chiral agent, and the pitch and reflection wavelength can be changed by adjusting the chiral agent with different HTP values ​​and the content in the liquid crystal material. A single cholesteric phase liquid crystal with a central reflection wavelength is mixed with an adhesive to prepare a liquid crystal material and poured into a certain area of ​​the handwriting film, and the area can display a single color. The central reflection wavelength of the liquid crystal material refers to the wavelength of light reflected by the handwriting film made of liquid crystal material.

[0050] There are two ways to implement pouring multiple colors of liquid crystal materials into the same position of the liquid crystal handwriting film. The first one is:

[0051] S211: firstly, mixing at least two liquid crystal materials with different central reflection wavelengths according to a predetermined mass percentage to obtain a mixed liquid crystal material;

[0052] S212: pouring the mixed liquid crystal material between the first substrate and the second substrate.

[0053] The second method is to inject at least two liquid crystal materials with different central reflection wavelengths into the same position between the first substrate and the second substrate 22 with transparent electrodes by moving the injection ports for injecting liquid crystal materials of different colors to the same injection position range for injection;

[0054] For example, five colors of liquid crystal materials are set, namely, cholesteric liquid crystal with a central reflection wavelength of 400nm, a visual color of purple, code: purple; cholesteric liquid crystal with a central reflection wavelength of 480nm, a visual color of blue, code: blue; cholesteric liquid crystal with a central reflection wavelength of 520nm, a visual color of green, code: green; cholesteric liquid crystal with a central reflection wavelength of 580nm, a visual color of yellow, code: yellow; cholesteric liquid crystal with a central reflection wavelength of 620nm, a visual color of orange, code: orange; cholesteric liquid crystal with a central reflection wavelength of 660nm, a visual color of red, code: red. Five liquid crystal material injection ports are set accordingly. The corresponding relationship between the five liquid crystal material injection ports and the injected liquid crystal colors is as follows: the first liquid crystal material injection port is used to inject purple liquid crystal material, the second liquid crystal material injection port is used to inject blue liquid crystal material, the third liquid crystal material injection port is used to inject green liquid crystal material, the fourth liquid crystal material injection port is used to inject yellow liquid crystal material, and the fifth liquid crystal material injection port is used to inject red liquid crystal material. The five injection ports are arranged in a row. The driving unit drives the liquid crystal material injection port to move along the arrangement direction, so that the first liquid crystal material injection port moves to the injection position range for injection, and then drives the second liquid crystal material injection port to move to the aforementioned injection position range for injection, and then moves the remaining injection ports one by one to the same injection position range for injection according to the aforementioned method, so that liquid crystal materials of different colors are distributed at the same position of the handwriting film. In this embodiment, the second liquid crystal injection port or any other liquid crystal injection port can also be moved to the same injection position range for injection after the first liquid crystal injection port is injected. In this embodiment, the color type of the liquid crystal material used for injection, the number of liquid crystal material injection ports, the order of arrangement of the liquid crystal material injection ports, and the order of injection of liquid crystal materials of different colors can be arbitrarily selected according to production needs and are not limited here.

[0055] After the liquid crystal materials with different central reflection wavelengths are mixed and coated on the handwriting film in different proportions, the handwriting film can display various colors. The liquid crystal materials with different central reflection wavelengths can be mixed in a preset proportion or in a random proportion, so that the proportions of the various liquid crystal materials finally coated on the handwriting film vary randomly with the position of the handwriting film, that is, the mass percentages of the liquid crystal materials with different central reflection wavelengths in the liquid crystal mixed material injected between the first substrate and the second substrate 22 vary randomly with the position of the liquid crystal handwriting film, so as to achieve the effect of randomly displaying rich colors and color changes on the handwriting film.

[0056] For example, a liquid crystal material that can display red when acting alone and a liquid crystal material that can display blue when acting alone are mixed together to obtain a mixed liquid crystal material. Then the mixed liquid crystal material is poured between the first substrate and the second substrate 22. The same position of the handwriting film produced in this way is coated with the above-mentioned two liquid crystal materials. The two liquid crystal materials can display various colors between red and blue when acting together. Since the proportions of the two liquid crystal materials at different positions are different, the colors displayed are also different. If the mixing degree of the two colors of liquid crystal materials is not deliberately controlled, the proportion of the two materials mixed at various positions of the handwriting film is random, so the color displayed by the manufactured handwriting film is also random, that is, the liquid crystal handwriting film manufactured by this device can display a disordered color effect. Although the above example only illustrates the mixing of liquid crystal materials of red and blue colors, it can be understood that this embodiment can also use liquid crystal materials of any other colors for mixing, and the number of mixed colors can also be any number, and the types and numbers of mixed colors are not limited here.

[0057] The first substrate and the second substrate 22 in S20 can be polyester film PET, polyvinyl chloride PVC, polycarbonate PC, etc., which are compounded with transparent electrode films, and have a thickness of 45-265μm. Transparent electrode layers are provided on both the first substrate and the second substrate. During the perfusion, the position of the perfusion port can be kept unchanged, so that the mixed liquid crystal material can be perfused into the set area of ​​the handwriting film, so that different positions of the set area can display the colors and color changes of the mixed liquid crystal materials. It is also possible to move the position of the perfusion port after a mixed liquid crystal material is perfused in a certain area of ​​the liquid crystal handwriting film, and perfuse other types of mixed liquid crystal materials on the liquid crystal handwriting film, so that different combinations of color changes can be formed on the liquid crystal handwriting film.

[0058] When mixing, different delivery channels can be used to deliver liquid crystal materials of different colors to the mixing channel, and then the mixed liquid crystal materials flow out of the mixing channel and drip directly onto the handwriting film. The liquid crystal materials of different colors are mixed by the flow channel, and the mixing can be carried out during the flow of the liquid crystal materials. The mixing and dripping efficiency is high, which can significantly improve the production efficiency. When mixing in the flow channel process, the degree of mixing of different materials is highly random, which can be used to manufacture a liquid crystal handwriting film with randomly distributed colors.

[0059] When the liquid crystal material is poured between the first substrate and the second substrate 22, the first substrate, the second substrate 22 and the mixed liquid crystal material are compounded into a liquid crystal handwriting film.

[0060] The specific composite method is to apply a first pressure toward the second substrate 22 on the side of the first substrate away from the second substrate 22, and at the same time apply a second pressure toward the first substrate on the side of the second substrate 22 away from the first substrate, and the first substrate, the second substrate 22 and the mixed liquid crystal material therebetween are pressed together to form a liquid crystal handwriting film by the first pressure and the second pressure. That is, pressure is applied on the outside of the two material layers, and the first substrate, the second substrate 22 and the mixed liquid crystal material are pressed together by rolling.

[0061] Example 2

[0062] In order to ensure the composite effect, the present embodiment utilizes a first pressing roller and a second pressing roller to press the first substrate and the second substrate 22 filled with a mixed liquid crystal material together. A pressing gap is formed between the first pressing roller and the second pressing roller. The first substrate and the second substrate 22 filled with a mixed liquid crystal material are pressed together when passing through the pressing gap. The mixed liquid crystal material moves from top to bottom toward the pressing gap. The position where the liquid crystal material is poured is located above the pressing gap.

[0063] During the compounding process, the first substrate and the second substrate 22 can be conveyed toward the lamination gap by a conveying device, and the lamination gap gradually narrows along the conveying direction of the first substrate and the second substrate 22, so that the first substrate and the second substrate 22 are gradually pressed together by the pressure of the pressing roller during the process of entering the lamination gap, thereby forming a liquid crystal handwriting film with a stable structure. Figure 2 As shown, the specific steps are:

[0064] S31: transporting the first substrate and the second substrate 22 to a lamination gap position,

[0065] S32: passing the first substrate and the second substrate 22 through the pressing gap to press the first substrate and the second substrate 22 together;

[0066] S33: rolling up the pressed liquid crystal handwriting film.

[0067] The pressure of the rollers acting on the first substrate and the second substrate 22 ranges from 0.1 MPa to 0.3 MPa, and the gap between the rollers ranges from 0.05 mm to 0.3 mm.

[0068] like Figure 3 As shown, in order to ensure that the mixed liquid crystal material can be poured into the preset position of the handwriting film, before S212, it also includes step S2111: determining the position of the mixed liquid crystal material pouring outlet according to the position of the color displayed on the handwriting film; S2112: moving the position of the mixed liquid crystal material pouring outlet to the predetermined pouring position.

[0069] In addition, the position of the mixed liquid crystal material injection outlet can be randomly moved in the injection position range along the direction parallel to the pressing gap. The injection position range can be set according to the area where the color to be displayed on the liquid crystal handwriting film is located. During the injection process, the position of the mixed liquid crystal material injection outlet is randomly moved in the direction parallel to the pressing gap, so that the proportions of different types of liquid crystal materials coated on the handwriting film can be randomly distributed on the handwriting film, thereby displaying various randomly changing colors.

[0070] In addition, during the pouring, the direction of the mixed liquid crystal material pouring is the same as the moving direction of the first substrate and the second substrate 22 when entering the lamination gap. Since the lamination gap gradually narrows along the direction in which the first substrate and the second substrate 22 are conveyed, the first substrate and the second substrate 22 are squeezed by the lamination gap during the process of entering the lamination gap, and the air remaining between the first substrate, the second substrate 22 and the mixed liquid crystal is squeezed out, so that the quality of the liquid crystal material after lamination is guaranteed.

[0071] In addition, the color difference of the handwriting film can be controlled by controlling the rotation speed of the coating roller, the amount of glue stored between the first and second pressing rollers, and the length of the mixing rubber tube used to mix different color liquid crystal materials during the compounding process. When the rotation speed of the first and second pressing rollers is between 0.02m / min and 0.85m / min, the color of the handwriting film obtained is the richest. When the amount of glue stored is controlled at 3ml to 10ml, the color of the handwriting film obtained is also relatively rich. For example, two colors of liquid crystal materials, blue with a central reflection wavelength of 420nm and yellow with a central reflection wavelength of 580nm, are used to make liquid crystal handwriting films. Among them, the length of the mixing rubber tube is 3cm, the rotation speed of the coating roller is 0.5m / min, and the amount of glue stored between the two rollers is about 5ml, which can obtain better gradient colors. The color gradient that can be distinguished by the naked eye is: from the 420nm band to the 480nm band, then to the 520nm band, then to the 550nm band, and then to the 580nm band.

[0072] like Figure 4 As shown, after S30, S40 is also included: using an external field to cure the mixed liquid crystal material located on the first substrate and the second substrate 22 to form a polymer dispersed liquid crystal. The applied external field can be heating, ions, ultraviolet light, etc. In this embodiment, ultraviolet light is preferably used to cure the mixed liquid crystal material. The adhesive in the corresponding liquid crystal material is an ultraviolet curing optical adhesive. The light intensity of the ultraviolet light curing during curing is 10mW / cm2, and the curing time is 6 minutes.

[0073] Example 3

[0074] like Figure 5As shown, this embodiment provides a liquid crystal handwriting film manufacturing device, the device includes a laminating device 10, including a first pressing roller 11 and a second pressing roller 12 whose axial directions of rotation are parallel to each other, a laminating gap 13 for a first substrate 21, a second substrate 22 and a liquid crystal injection material to pass through is formed between the first pressing roller 11 and the second pressing roller 12, and the laminating device 10 is configured to press the first substrate 21, the second substrate 22 and the liquid crystal injection material together when they pass through the gap to form a liquid crystal handwriting film;

[0075] During the manufacturing process of the liquid crystal handwriting film, the relevant conveying mechanism conveys the first substrate 21 and the second substrate 22 to the lamination gap 13 of the lamination device 10. The first substrate 21 and the second substrate 22 can be a PET film or a PC film compounded with a transparent electrode film. At the same time, the driving mechanism drives the first pressing roller 11 and the second pressing roller 12 to rotate towards each other, wherein the rotation axis directions of the first pressing roller 11 and the second pressing roller 12 are both perpendicular to the conveying direction when the first substrate 21 and the second substrate 22 are conveyed to the lamination gap 13. While the first substrate 21 and the second substrate 22 move toward the lamination gap 13, the liquid crystal material injection device injects the liquid crystal material between the first substrate 21 and the second substrate 22. When the first substrate 21, the second substrate 22 and the liquid crystal material pass through the lamination gap 13 between the first pressing roller 11 and the second pressing roller 12, the first substrate 21, the second substrate 22 and the liquid crystal material between the two are tightly attached together by the rolling action of the two pressing rollers to form a liquid crystal handwriting film with a stable structure.

[0076] The liquid crystal material pouring device 30 includes a liquid crystal material conveying unit, a liquid crystal material mixing unit and a liquid crystal material pouring port 33. The liquid crystal material conveying unit is connected to the liquid crystal material mixing unit, and the liquid crystal material mixing unit is connected to the liquid crystal material pouring port 33. The liquid crystal material conveying unit is configured to convey at least two liquid crystal materials of different colors to the liquid crystal material mixing unit, and the liquid crystal material mixing unit is configured to mix at least two liquid crystal materials of different colors together. The liquid crystal material pouring port 33 is configured to pour the liquid crystal material mixed by the liquid crystal material mixing unit into between the first substrate 21 and the second substrate 22.

[0077] The liquid crystal injection device in this embodiment has a liquid crystal material mixing unit added between the liquid crystal material delivery unit and the liquid crystal material injection port 33. Before injection, the type of liquid crystal material to be mixed can be determined first. For example, if it is necessary to mix liquid crystal materials that can display red and liquid crystal materials that can display blue, the liquid crystal material delivery unit is used to deliver the liquid crystal material that can display red and the liquid crystal material that can display blue to the liquid crystal material mixing unit. In the liquid crystal material mixing unit, the liquid crystal material that can display red and the liquid crystal material that can display blue are mixed together. Finally, the liquid crystal material injection port 33 injects the mixed liquid crystal material between the first substrate 21 and the second substrate 22. The same position of the handwriting film produced in this way is coated with the above-mentioned two liquid crystal materials, and the proportions of the two liquid crystal materials at different positions are different, and the colors displayed are also different. Therefore, the liquid crystal handwriting film produced by this device can display various colors between the above-mentioned two colors. If the mixing degree of the two colors of liquid crystal materials is not deliberately controlled, the mixing ratio of the two materials at each position of the handwriting film is random, so the color displayed by the manufactured handwriting film is also random, that is, the liquid crystal handwriting film manufactured by the present device can display a disordered color effect. Although the above example only describes the mixing of red and blue liquid crystal materials, it can be understood that the present embodiment can also use any other color of liquid crystal materials for mixing, and the number of the mixed colors can also be any number, and the types and numbers of the mixed colors are not limited here.

[0078] like Figure 6 and Figure 7 As shown, in this embodiment, the liquid crystal material delivery unit includes a plurality of delivery channels 31, each delivery channel 31 is configured to deliver a liquid crystal material of a corresponding color to the liquid crystal material mixing unit, wherein at least two delivery channels 31 deliver liquid crystal materials of different colors.

[0079] In order to be able to transport liquid crystal materials of various colors, the liquid crystal material transport unit of this embodiment adopts the form of a combination of multiple transport channels 31. Each transport channel 31 only transports liquid crystal materials of one color. The same color of liquid crystal material can be transported by one transport channel 31 or by multiple transport channels 31.

[0080] For example, the liquid crystal material delivery unit includes four delivery channels, namely, a first delivery channel, a second delivery channel, a third delivery channel and a fourth delivery channel. The liquid crystal material delivery unit needs to deliver four colors of liquid crystal materials, wherein the first delivery channel delivers the first color of liquid crystal material, the second delivery channel delivers the second color of liquid crystal material, the third delivery channel delivers the third color of liquid crystal material, and the fourth delivery channel delivers the fourth color of liquid crystal material.

[0081] For another example, the liquid crystal material delivery unit includes four delivery channels 31, namely, a first delivery channel, a second delivery channel, a third delivery channel and a fourth delivery channel. The liquid crystal material delivery unit needs to deliver three colors of liquid crystal materials, wherein the first delivery channel delivers the first color of liquid crystal material, the second delivery channel delivers the first color of liquid crystal material, the third delivery channel delivers the second color of liquid crystal material, and the fourth delivery channel delivers the third color of liquid crystal material.

[0082] For another example, the liquid crystal material delivery unit includes four delivery channels, namely, a first delivery channel, a second delivery channel, a third delivery channel and a fourth delivery channel. The liquid crystal material delivery unit needs to deliver two colors of liquid crystal materials, wherein the first delivery channel delivers the liquid crystal material of the first color, the second delivery channel delivers the liquid crystal material of the first color, the third delivery channel delivers the liquid crystal material of the second color, and the fourth delivery channel delivers the liquid crystal material of the second color.

[0083] For another example, the liquid crystal material delivery unit includes four delivery channels, namely, a first delivery channel, a second delivery channel, a third delivery channel and a fourth delivery channel. The liquid crystal material delivery unit needs to deliver two colors of liquid crystal materials, wherein the first delivery channel delivers the liquid crystal material of the first color, the second delivery channel delivers the liquid crystal material of the first color, the third delivery channel delivers the liquid crystal material of the first color, and the fourth delivery channel delivers the liquid crystal material of the second color.

[0084] In addition, the liquid crystal material mixing unit of this embodiment includes at least one mixing channel 32 , and the mixing channel 32 is configured to communicate with the delivery channel 31 corresponding to the liquid crystal material to be mixed.

[0085] In this embodiment, the liquid crystal material mixing unit adopts the form of a mixing channel 32, so that liquid crystal materials of different colors can be quickly mixed in the flow channel process, which not only significantly improves the production efficiency of the handwriting film manufacturing equipment, but also improves the randomness of the mixing ratio of liquid crystal materials of various colors on the handwriting film, so that the effect of disordered color distribution of the liquid crystal handwriting film is further enhanced.

[0086] In other embodiments, the liquid crystal material mixing unit may also adopt other structures or components that can mix liquid crystal materials of different colors, such as a structure or component having a receiving cavity that communicates with a liquid crystal material delivery unit that can deliver multiple colors and can accommodate liquid crystal materials of multiple colors, or a pipeline structure that communicates with a liquid crystal material delivery unit that can deliver multiple colors.

[0087] In this embodiment, the mixing channel 32 is configured to be connected to the delivery channel 31 corresponding to the liquid crystal material to be mixed. For example, one of the mixing channels 32 needs to mix the liquid crystal material of the first color, the liquid crystal material of the second color and the liquid crystal material of the third color. At this time, the mixing channel 32 is connected to the corresponding delivery channel 31 for delivering the liquid crystal material of the first color, the delivery channel for delivering the liquid crystal material of the second color and the delivery channel for delivering the liquid crystal material of the third color.

[0088] The way to connect the mixing channel 32 with the delivery channel 31 corresponding to the liquid crystal material to be mixed can be to directly connect the corresponding delivery channel 31 with the mixing channel 32 by using a pipeline or a pipe. For example, the liquid crystal material mixing unit has two mixing channels 32, namely the first mixing channel and the second mixing channel. The first mixing channel needs to mix the liquid crystal material of the first color and the liquid crystal material of the second color, and the second mixing channel needs to mix the liquid crystal material of the second color and the liquid crystal material of the third color. The first mixing channel is connected to the delivery channel 31 for conveying the first color liquid crystal material and the delivery channel 31 for conveying the second color liquid crystal material through a pipeline, and the second mixing channel is directly connected to the delivery channel 31 for conveying the second color liquid crystal material and the delivery channel 31 for conveying the third color liquid crystal material through a pipeline. The pipeline connected to the aforementioned mixing channel 32 can be a three-way pipeline, a four-way pipeline, or other connecting pipelines with any number of interfaces. When the length of the mixing channel is between 0.1 cm and 7 cm, a handwriting film with richer colors can be obtained.

[0089] It is understandable that the number of the delivery channels 31 and the distribution of the liquid crystal mixing channels 32 and the delivery channels 31 can be set according to the type of liquid crystal material that needs to be mixed, and the specific number is not limited here.

[0090] In addition to the aforementioned communication method between the mixing channel 32 and the corresponding delivery channel 31 , this embodiment also provides other communication methods.

[0091] Specifically, the liquid crystal material mixing unit includes at least one mixing channel 32, and the mixing channel 32 is connected to a plurality of delivery channels 31 through an on-off control device, and the on-off control device is used to control the connection and disconnection between the mixing channel 32 and the delivery channel 31. The on-off control device is configured to control the mixing channel 32 to be connected to the delivery channel 31 corresponding to the liquid crystal material to be mixed, and to be disconnected from the remaining delivery channels 31.

[0092] like Figure 7 As shown, in this embodiment, each delivery channel 31 is pre-connected with each mixing channel 32 via an on-off control device, wherein the on-off control device may be a pipeline with a switch valve 34 .

[0093] For example, the liquid crystal material mixing unit has two mixing channels 32, namely, a first mixing channel and a second mixing channel. The first mixing channel needs to mix the liquid crystal material of the first color and the liquid crystal material of the second color, and the second mixing channel 32 needs to mix the liquid crystal material of the second color and the liquid crystal material of the third color. The first mixing channel 32 and the second mixing channel 32 can be connected in advance with the delivery channel 31 for delivering the first color liquid crystal material, the delivery channel 31 for delivering the second color liquid crystal material, and the delivery channel 31 for delivering the third color, respectively, by using an on-off control device.

[0094] When the mixed liquid crystal material is poured into the first mixing channel 32, the valve 34 between the first mixing channel 32 and the delivery channel 31 for conveying the first color liquid crystal material is opened to connect the first mixing channel 32 with the delivery channel 31 for conveying the first color liquid crystal material. At the same time, the valve 34 between the first mixing channel 32 and the delivery channel 31 for conveying the second color liquid crystal material is opened to connect the first mixing channel 32 with the delivery channel 31 for conveying the second color liquid crystal material, and the valve 34 between the first mixing channel 32 and the delivery channel 31 for conveying the third color liquid crystal material is closed. In this way, only the liquid crystal material of the first color and the liquid crystal material of the second color can enter the first mixing channel 32 through the corresponding delivery channels for mixing.

[0095] When the mixed liquid crystal material is poured into the second mixing channel 32, the valve 34 between the second mixing channel 32 and the delivery channel 31 for conveying the second color liquid crystal material is opened to connect the second mixing channel 32 with the delivery channel 31 for conveying the second color liquid crystal material. At the same time, the valve 34 between the second mixing channel 32 and the delivery channel 31 for conveying the third color liquid crystal material is opened to connect the second mixing channel 32 with the delivery channel 31 for conveying the third color liquid crystal material, and the valve 34 between the first mixing channel 32 and the delivery channel 31 for conveying the first color liquid crystal material is closed. In this way, only the second color liquid crystal material and the third color liquid crystal material can enter the second mixing channel 32 through the corresponding delivery channels for mixing.

[0096] By adopting the above solution, when the type of liquid crystal material to be mixed in the mixing channel 32 changes, there is no need to change the connection method of the original pipeline, so that more flexible production can be achieved.

[0097] The valves 34 controlling the on-off of each flow channel may be common valves 34 , and operators may open or close each valve 34 according to the production process to control the on-off of each valve 34 .

[0098] In addition, in order to improve the degree of automation, the valves 34 controlling the on-off of each flow channel can also be electrically controlled valves 34, and configured with corresponding controllers, such as PLC, industrial computer, embedded control system, etc. The signal output end of the controller is connected to the control signal input end of each electrically controlled valve 34, and the controller can generate a control signal according to the process requirements to automatically control the on-off status of each valve 34, thereby controlling the type of liquid crystal material entering each mixing flow channel 32 for mixing.

[0099] In specific implementation, each delivery channel 31 can be connected to a liquid crystal material source of a corresponding color. For example, different types of liquid crystal materials can be stored in different storage containers, and then each delivery channel 31 can be connected to a corresponding storage container according to the color of the liquid crystal material. In order to allow the liquid crystal material to be transported to the mixing channel 32 through the delivery channel 31, a pump can also be provided in this embodiment to pump the liquid crystal material.

[0100] In this embodiment, a first driving device 35 is further included, and the driving device is used to drive the liquid crystal material injection port 33 to move so that the outlet of the liquid crystal material injection port 33 from which the corresponding liquid crystal material drips out is located at a set injection position.

[0101] In this embodiment, a pouring head may be configured for each mixing channel 32 in the liquid crystal material mixing unit, and the liquid crystal material mixed by the mixing unit is poured between the two layers of material by the pouring head.

[0102] In other embodiments, an integrated structure of a liquid crystal material mixing unit and a liquid crystal material injection port 33 may be adopted, and the mixing channel 32 is used to mix different types of liquid crystal materials and inject the mixed liquid crystal material at the same time. In this way, one end of the mixing channel 32 is used to receive different types of liquid crystal materials, and the other end forms a liquid crystal material injection port 33 for injecting the mixed liquid crystal material.

[0103] Regardless of the form of the liquid crystal material injection port 33, the position where the liquid crystal material drips out from the liquid crystal material injection device 30 is preferably the side where the first substrate 21 and the second substrate 22 of the two pressing rollers enter the pressing gap 13.

[0104] like Figure 8 and Fig. 9As shown, in this embodiment, the first driving device 35 is used to drive the liquid crystal material injection port 33 to move, so that the pre-set injection port for injecting the corresponding mixed liquid crystal material is located at the correct injection position. For example, the liquid crystal material injection device 30 is provided with a first injection port, a second injection port and a third injection port, which are used to inject the first mixed liquid crystal material, the second mixed liquid crystal material and the third mixed liquid crystal material respectively. If the current process needs to inject the second mixed liquid crystal material into the first substrate 21 and the second substrate 22, then the first driving device 35 drives the second injection port to move to the position just above the pressing gap 13, and then the second mixed liquid crystal material flows out from the second injection port to between the first substrate 21 and the second substrate 22. Fig. 9 The direction of the middle arrow is the moving direction of the liquid crystal material injection port 33 .

[0105] The liquid crystal material filling device 30 may be provided with one filling port or multiple filling ports. When multiple filling ports are provided, the multiple filling ports may be arranged in a row along a direction parallel to the pressing gap 13. The first driving device 35 drives the row of filling ports to move back and forth along a direction parallel to the pressing gap 13 so that the corresponding filling port among the multiple filling ports is located at the set filling position.

[0106] In this embodiment, multiple pouring heads may be provided, each of which is connected to a mixing channel 32, a pouring port is formed on the delivery pouring head, and multiple pouring heads are arranged along a first direction, and the first driving device 35 is used to drive the multiple pouring heads to move along the first direction so that the corresponding pouring heads move to the pouring position. The first direction may be a direction parallel to the pressing gap 13.

[0107] The injection port can move along a straight line or rotate around a center. Fig.10 As shown, the multiple injection ports are arranged at different circumferential positions of the same circle. The first driving device 35 drives the multiple injection ports to rotate along the circle, and moves the injection port corresponding to the mixed liquid crystal material currently required to be injected to the preset injection position. Fig.10 The direction of the middle arrow is the rotation direction of the liquid crystal material injection port 33.

[0108] The first driving device 35 can drive each filling port to move synchronously, or can drive each filling port to move independently.

[0109] In the present application, the first substrate 21 and the second substrate 22 may enter the pressing gap 13 along a vertical direction or along a horizontal direction.

[0110] In this embodiment, a flow control device can also be used to control the flow rate of liquid crystal materials of various colors flowing into the liquid crystal material mixing unit, thereby controlling the ratio of various liquid crystal materials in the mixed liquid crystal material, and finally controlling the color displayed by the liquid crystal handwriting film. The flow control device can be a valve 34 installed between each delivery channel 31 and the mixing channel 32 that can control the flow rate. The flow control device can also be used to control the flow rate of liquid crystal materials of various colors flowing into the liquid crystal material mixing unit, thereby controlling the mixing degree of liquid crystal materials of different colors to control the color of the handwriting film.

[0111] In addition, if Fig.11 As shown, this embodiment is further provided with an ultraviolet curing device 40, which uses the external light generated by the ultraviolet curing device 40 to irradiate the curing glue in the liquid crystal material during the lamination process, so that the liquid crystal glue is quickly cured, which helps the liquid crystal handwriting film to be quickly formed.

[0112] like Fig.12 As shown, in order to make the first substrate 21 and the second material well pressed together, the present embodiment further provides a pressure control device, which is used to control the pressure applied by the first pressing roller 11 and the second pressing roller 12 to the first substrate 21 and the second substrate 22 during the pressing process. The pressure control device includes a controller, a pressure sensor and a pressing roller spacing adjustment mechanism. The controller controls the pressing roller spacing adjustment mechanism to adjust the size of the pressing gap 13 according to the pressure applied by the first pressing roller 11 and the second pressing roller 12 to the liquid crystal handwriting film detected by the pressure sensor. When the detected pressure is less than the preset pressure, the controller controls the spacing adjustment mechanism to drive the first pressing roller 11 and the second pressing roller 12 to approach each other, so that the pressing gap 13 is reduced, thereby increasing the total pressure during the pressing process, and vice versa.

[0113] In addition, in order to continuously convey the first substrate 21 and the second substrate 22 to the laminating device 10, the present embodiment may further provide a first unloading device 50 for rolling up the first substrate 21 on the material entry side of the pressure roller, and a second unloading device 60 for rolling up the second substrate 22, and a winding mechanism 70 is provided on the material delivery side of the pressure roller to roll up the laminated liquid crystal handwriting film.

[0114] As another embodiment, the liquid crystal injection device includes a liquid crystal material delivery unit, a plurality of liquid crystal material injection ports, and a driving unit, wherein the liquid crystal material delivery unit is configured to deliver at least two liquid crystal materials of different colors to the liquid crystal material injection ports, each liquid crystal material injection port corresponds to a liquid crystal material of a color, and the colors of the liquid crystal materials corresponding to at least two liquid crystal material injection ports are different, and the driving unit is configured to drive the liquid crystal material injection port to the injection position. In this embodiment, a plurality of liquid crystal material injection ports can be provided, and each liquid crystal material injection port is used to drop a liquid crystal material of a color.

[0115] In addition, it also includes a speed control device, which is used to control the speeds of the first pressing roller and the second pressing roller. By controlling the speeds of the two pressing rollers, the degree of mixing of liquid crystal materials of different colors can be controlled, thereby controlling the richness of the color of the handwriting film.

[0116] In addition, the color difference of the handwriting film can be controlled by controlling the rotation speed of the coating roller, the amount of glue stored between the first and second pressing rollers, and the length of the mixing rubber tube used to mix different color liquid crystal materials during the compounding process. When the rotation speed of the first and second pressing rollers is between 0.02m / min and 0.85m / min, the color of the handwriting film obtained is the richest. When the amount of glue stored is controlled at 3ml to 10ml, the color of the handwriting film obtained is also relatively rich. For example, two colors of liquid crystal materials, blue with a central reflection wavelength of 420nm and yellow with a central reflection wavelength of 580nm, are used to make liquid crystal handwriting films. The length of the mixing rubber tube is 3cm, the rotation speed of the coating roller is 0.5m / min, and the amount of glue stored between the two rollers is about 5ml, so that better gradient colors can be obtained. The color gradient that can be distinguished by the naked eye is: from the 420nm band to the 480nm band, then to the 520nm band, then to the 550nm band, and then to the 580nm band.

[0117] Example 4

[0118] like Fig.13 As shown, this embodiment provides a handwriting film whose color can be changed arbitrarily with position, comprising a first conductive layer 1, a second conductive layer 2 and a liquid crystal layer 3, wherein the first conductive layer 1 and the second conductive layer 2 are arranged opposite to each other, the liquid crystal layer 3 is located between the first conductive layer 1 and the second conductive layer 2, and the liquid crystal layer 3 comprises cholesteric phase liquid crystal and an adhesive;

[0119] In at least a portion of the handwriting film, at least two different types of cholesteric phase liquid crystals are mixed at the same position in the liquid crystal layer 3, and the mass percentages of at least two of the cholesteric phases change with the position of the handwriting film, and the central reflection wavelengths of the different cholesteric phase liquid crystals are different.

[0120] In this embodiment, the first conductive layer 1 and the second conductive layer 2 are used as electrodes. If the first conductive layer 1 and the second conductive layer 2 are energized, a certain voltage is generated between the first conductive layer 1 and the second conductive layer 2, and an electric field of a certain strength is formed between the first conductive layer 1 and the second conductive layer 2. Under the action of the electric field, the liquid crystal molecules in the liquid crystal layer 3 can be transformed from the P state to the FC state. The first conductive layer 1 and the second conductive layer 2 can be made of transparent electrodes such as ITO electrodes. The adhesive can be a UV curable adhesive.

[0121] In at least a portion of the handwriting film, at least two different types of cholesteric phase liquid crystals are mixed at the same position in the liquid crystal layer 3. The aforementioned at least a portion of the region may be only a portion of the handwriting film, or may include the entire region of the handwriting film, may be a continuous region, or may be a plurality of independent regions, and may be specified according to specific application requirements, and is not limited here.

[0122] In addition, the handwriting film in this embodiment may also include a transparent substrate layer 4 and a background color substrate layer that are arranged relatively, wherein the transparent substrate layer is located on the side of the first conductive layer 1 that is away from the liquid crystal layer 3, and the background color substrate layer is located on the side of the second conductive layer 2 that is away from the liquid crystal layer 3. The transparent substrate layer 4 and the background color substrate layer can be made of PET film or PC film. When the cholesteric liquid crystal is in the FC state, light passes through the transparent substrate layer 4, the first transparent electrode and the liquid crystal layer 3 and then irradiates the background color substrate layer. At this time, the user can only see the color of the background color substrate layer. When the background color substrate layer is black, the light is absorbed by the background color substrate layer, so the user sees a black handwriting film. In addition to black, the background color substrate layer can also be made of materials of other colors.

[0123] Different types of cholesteric phase liquid crystals in this application refer to cholesteric phase liquid crystals with different central reflection wavelengths. A single chiral agent and nematic phase liquid crystal can form a cholesteric phase liquid crystal that reflects a certain wavelength of light after being prepared in a fixed ratio, so that the handwriting film displays a single color. In this embodiment, a variety of cholesteric phase liquid crystals that can only display one color are mixed to the same position of the handwriting film, so that the position can display the color effect of the combined effect of the mixed cholesteric phase liquid crystals. The color displayed at this position is related to the mass percentage of various cholesteric phase liquid crystals. As the mass percentage of various cholesteric phase liquid crystals continues to change, the color displayed by the handwriting film also changes continuously. Therefore, the color that the handwriting film of this embodiment can display is far richer than the color displayed by various cholesteric phase liquid crystals acting alone. Moreover, in this embodiment, the mass percentage of various cholesteric phase liquid crystals changes continuously with the position of the writing board, so the user can not only see richer colors in the same area of ​​the handwriting board or on the entire handwriting board, but also see richer color changes.

[0124] This embodiment takes two types of cholesteric phase liquid crystals as an example to illustrate the handwriting film of the present application. In this embodiment, the cholesteric phase liquid crystal includes a first cholesteric phase liquid crystal and a second cholesteric phase liquid crystal;

[0125] The cholesteric phase liquid crystal includes a first cholesteric phase liquid crystal with a central reflection wavelength range of 420 to 480 nm and a second cholesteric phase liquid crystal with a central reflection wavelength of 600 nm;

[0126] The first cholesteric phase liquid crystal includes a nematic phase liquid crystal with Δn=0.3, a first chiral agent S811 and a second chiral agent S5011, and the mass percentages of the nematic phase liquid crystal, the first chiral agent S811 and the second chiral agent S5011 are 80% to 92%, 17% to 19.9%, and 0.1% to 3% respectively;

[0127] The second cholesteric phase liquid crystal includes a nematic phase liquid crystal with Δn=0.3, a first chiral agent S811 and a third chiral agent S2011, and the mass percentages of the nematic phase liquid crystal, the first chiral agent S811 and the third chiral agent S2011 are 80%, 11% and 9% respectively.

[0128] For example, when the first cholestatic phase liquid crystal acts alone, the handwriting film only displays yellow, and its corresponding central reflection wavelength is 580nm; when the second cholestatic phase liquid crystal acts alone, the handwriting film only displays blue, and its corresponding central reflection wavelength is 420nm. When the first cholestatic phase liquid crystal and the second cholestatic phase liquid crystal are mixed at the same position of the handwriting film so that they act at the same time, the color with the central reflection wavelength between 420nm and 580nm can be displayed. With the change of the mass percentage of the first cholestatic phase liquid crystal and the second cholestatic phase liquid crystal, the color that can be displayed on the handwriting film also changes continuously between the wavelength band, thereby displaying various colors between yellow and blue.

[0129] The two different cholesteric phase liquid crystals in this embodiment can also be cholesteric phase liquid crystals that display other colors when acting alone, such as a cholesteric phase liquid crystal that displays green and a cholesteric phase liquid crystal that displays red, or a cholesteric phase liquid crystal that displays green and a cholesteric phase liquid crystal that displays blue. The specific type of cholesteric phase liquid crystal can be selected as needed and is not limited here. For example, a liquid crystal with a blue band range of 420-480nm, a nematic phase liquid crystal with Δn=0.3, and a nematic phase liquid crystal ratio of more than 80%, can select a chiral agent S811 addition ratio of 17%-19.9%, and a chiral agent S5011 addition ratio of 0.1%-3%.

[0130] This embodiment uses three different cholesteric phase liquid crystals to mix and act at the same position to achieve more color displays and richer color changes.

[0131] In this embodiment, the cholestatic liquid crystal includes a first cholestatic liquid crystal, a second cholestatic liquid crystal and a third cholestatic liquid crystal;

[0132] The first cholesteric phase liquid crystal is a cholesteric phase liquid crystal with a central reflection wavelength of 480nm, which makes the handwriting color of the handwriting board blue, the proportion of nematic phase liquid crystal with Δn=0.3 is 80%, the addition ratio of chiral agent S811 is 19.6%, and the addition ratio of chiral agent S5011 is 0.4%.

[0133] The second cholesteric phase liquid crystal is a cholesteric phase liquid crystal with a central reflection wavelength of 520nm, which makes the handwriting color of the handwriting board green, the proportion of nematic phase liquid crystal with Δn=0.3 is 80%, the addition ratio of chiral agent S811 is 19.85%, and the addition ratio of chiral agent S5011 is 0.15%.

[0134] The third cholesteric phase liquid crystal is a cholesteric phase liquid crystal with a central reflection wavelength of 600nm, which makes the handwriting color of the handwriting board red, the proportion of the nematic phase liquid crystal with Δn=0.3 is 80%, the addition ratio of the chiral agent S811 is 11%, and the addition ratio of the chiral agent S2011 is 9%.

[0135] When the first type of cholestatic liquid crystal acts alone, the handwriting film displays blue cholestatic liquid crystal, when the second type of cholestatic liquid crystal acts alone, the handwriting film displays green cholestatic liquid crystal, and when the third type of cholestatic liquid crystal acts alone, the handwriting film displays red cholestatic liquid crystal. When the three types of cholestatic liquid crystals are mixed at the same position of the handwriting film and act together, the color effect of the three colors mixed can be displayed. When the mass percentages of the three types of cholestatic liquid crystals are constantly changing, the color displayed by the handwriting film will also change continuously. The way the mass percentages of the three types of cholestatic liquid crystals change can be any two of them, the other one remains unchanged, or all three change at the same time. It can be understood that in other embodiments, the types of cholestatic liquid crystals can be extended to any number, for example, n types, n is a natural number and n≥2, and the mass percentages of any m types of cholestatic liquid crystals vary with the position, where m is a natural number, 2≥m≥n.

[0136] As a preferred embodiment, the cholesteric phase liquid crystal includes a first cholesteric phase liquid crystal and a second cholesteric phase liquid crystal, the first cholesteric phase liquid crystal central reflection wavelength is λ1, the second cholesteric phase liquid crystal central reflection wavelength is λ2, assuming d=|λ1-λ2|, d≥80nm. When the central reflection wavelength between the two cholesteric phase liquid crystals meets the above range, the color difference of the handwriting film produced by this method is more varied.

[0137] This embodiment describes a handwriting film that can achieve different color change modes.

[0138] As an example, the mass percentage of various cholesteric phase liquid crystals in this embodiment can be changed in any direction on the handwriting film, or can be changed along certain predetermined directions on the handwriting film. In this way, the color of the handwriting film can also be changed along the aforementioned predetermined directions to have rich colors.

[0139] The direction of change can be any straight line direction or any curved line direction, or can be changed along a broken line composed of straight lines in different directions, or along a direction change composed of straight lines and curves in different directions.

[0140] The mass percentages of various cholesteric phase liquid crystals can be changed along a predetermined direction or along multiple different directions at the same time. The specific changing method can be set according to the actual situation. Different changing methods of the mass percentages of cholesteric phase liquid crystals can form handwriting films with different color changes, making the color changes of the handwriting films more abundant.

[0141] In addition, the mass percentages of various cholesteric phase liquid crystals in this embodiment can also be changed randomly with the position, so that the colors appearing at various positions of the handwriting film are random, and the colors seen by the user after touching the handwriting film with hands or other tools are randomly changed, which can achieve the effect of disordered colors. Compared with the method of displaying only one color in a region in the prior art, the handwriting film of this embodiment has richer color changes, and the fun of the handwriting board has been significantly improved.

[0142] In addition, in this embodiment, various forms of random changes can be adopted, such as the mass percentage of various cholesteric phase liquid crystals randomly changing along a certain direction or randomly changing along multiple directions at the same time, or the direction of change is also random. For example, among a variety of cholesteric phase liquid crystals, the types of cholesteric phase liquid crystals whose mass percentage changes with position are random, or the number of types of cholesteric phase liquid crystals whose mass percentage changes with position is randomly generated. In this way, color display that changes randomly in various ways can be achieved on the handwriting board.

[0143] In addition, in this embodiment, the mass percentage of various cholesteric phase liquid crystals may vary with position in a jumpy or continuous manner.

[0144] The mass percentage of various cholesteric phase liquid crystals can be continuously changed to make the handwriting board display continuously changing colors, so that the displayed colors are the richest. The mass percentage of various cholesteric phase liquid crystals can be continuously changed in the aforementioned direction. A random continuous change method can also be adopted. For example, the rate of change of the mass percentage of various cholesteric phase liquid crystals changes randomly with the handwriting film. In this way, the handwriting board can display the richest colors and different colors can appear on the handwriting board in a random changing manner. The fun of the handwriting board is also further increased.

[0145] Example 5

[0146] This embodiment provides an electronic writing device, which includes a control circuit and a handwriting film as described in Example 4 whose color changes arbitrarily with position, wherein the control circuit is used to apply a voltage signal to the first conductive layer 1 and the second conductive layer 2 to switch the liquid crystal layer 3 between the FC state and the P state.

[0147] The electronic writing device of this embodiment is made of the handwriting film of the above embodiment. When the cholestatic liquid crystal is in the FC state, the liquid crystal handwriting board only displays the color of the black substrate layer from the appearance, and the position of the handwriting film under pressure is converted from the FC state to the P state. The handwriting film at this position reflects a certain band of light, so that the user can see the lines or traces of the corresponding color. When the control circuit applies a voltage exceeding a certain threshold to the first electrode layer and the second electrode layer, the electric field formed between the first electrode layer and the second electrode layer, which was originally in the P state, is converted from the cholestatic liquid crystal to the FC state, and the color traces on the handwriting film are removed.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for manufacturing a liquid crystal handwriting film, characterized in that: The following steps are involved: S10: preparing at least two liquid crystal materials with different central reflection wavelengths; S20: injecting at least two liquid crystal materials with different central reflection wavelengths into the same position between the first substrate and the second substrate to obtain a mixed liquid crystal material mixed according to a predetermined mass percentage, wherein a first transparent electrode is provided on a surface of the first substrate facing the second substrate, and a second transparent electrode is provided on a surface of the second substrate facing the first substrate; S30: Compounding the first substrate, the second substrate, and the mixed liquid crystal material between the first substrate and the second substrate into a liquid crystal handwriting film; The S20 further includes the following steps: S211: firstly, mixing at least two liquid crystal materials with different central reflection wavelengths according to a predetermined mass percentage to obtain a mixed liquid crystal material; S212: pouring the mixed liquid crystal material between the first substrate and the second substrate; In S212: when the mixed liquid crystal material is poured between the first substrate and the second substrate, the mass percentage of liquid crystal materials with different central reflection wavelengths in the mixed liquid crystal material poured between the first substrate and the second substrate varies randomly with the position of the liquid crystal handwriting film.

2. The method for manufacturing a liquid crystal handwriting film according to claim 1, characterized in that: The step S20 includes: moving each injection port for injecting liquid crystal materials with different central reflection wavelengths to the same injection position for injection according to a predetermined time sequence.

3. The method for manufacturing a liquid crystal handwriting film according to claim 1, characterized in that: The liquid crystal material includes Cholesterol Phase liquid crystal and an adhesive, wherein the cholesteric phase liquid crystal includes a nematic phase liquid crystal and a chiral agent for adjusting the central reflection wavelength of the cholesteric phase liquid crystal.

4. The method for manufacturing a liquid crystal handwriting film according to claim 3, characterized in that: The cholesteric liquid crystal includes a first cholesteric liquid crystal and a second cholesteric liquid crystal, the central reflection wavelength of the first cholesteric liquid crystal is λ1, the central reflection wavelength of the second cholesteric liquid crystal is λ2, and d=|λ1-λ2|, d≥80nm.

5. The method for manufacturing a liquid crystal handwriting film according to claim 1, characterized in that: In S211, the flow rate of at least one liquid crystal material with a central reflection wavelength is reduced from a first preset flow rate to a second preset flow rate, wherein the first preset flow rate value is greater than the second preset flow rate value.

6. The method for manufacturing a liquid crystal handwriting film according to claim 1, characterized in that: After S30, the method further includes S40: curing the mixed liquid crystal material located on the first substrate and the second substrate by using an external field to form a polymer dispersed liquid crystal.

7. A liquid crystal handwriting film manufacturing device for implementing the liquid crystal handwriting film manufacturing method according to any one of claims 1 to 6, characterized in that: include: A liquid crystal material mixing and pouring device, the liquid crystal material mixing and pouring device is used to mix at least two different types of liquid crystal materials and then pour them into the same position of the liquid crystal handwriting film, or to pour at least two different types of liquid crystal materials into the same position of the liquid crystal handwriting film and then mix them; A laminating device, the laminating device comprising a first pressing roller and a second pressing roller, the rotation axes of the first pressing roller and the second pressing roller are parallel, and the first pressing roller and the second pressing roller are spaced a preset distance apart to press the liquid crystal handwriting film; The laminating device is used to control the first pressing roller and the second pressing roller to rotate in opposite directions to laminar the liquid crystal handwriting film after the liquid crystal material mixing and filling device has filled the liquid crystal material.

8. The liquid crystal handwriting film manufacturing equipment according to claim 7, characterized in that: The rotation speeds of the first pressing roller and the second pressing roller are 0.25 m / min to 0.85 m / min.

Images