CN111367107A

CN111367107A - Method and equipment for manufacturing liquid crystal handwriting film

Info

Publication number: CN111367107A
Application number: CN202010144074.8A
Authority: CN
Inventors: 陈昭宇; 陈旭航
Original assignee: Guangdong Duote Photoelectric Technology Co ltd
Current assignee: Guangdong Duote Photoelectric Technology Co ltd
Priority date: 2020-03-04
Filing date: 2020-03-04
Publication date: 2020-07-03

Abstract

The invention provides a manufacturing method and manufacturing equipment of a liquid crystal handwriting film, and relates to the technical field of liquid crystal handwriting films. The manufacturing method of the liquid crystal handwriting film comprises the following steps of 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 the first substrate and the second substrate; s30: and 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 liquid crystal handwriting film manufacturing equipment comprises: the liquid crystal material mixing and filling device is used for mixing different types of liquid crystal materials and then filling the liquid crystal materials to the same position of the liquid crystal handwriting film or filling different types of liquid crystal materials to the same position of the liquid crystal handwriting film and then mixing the liquid crystal materials. The method and the device for manufacturing the liquid crystal handwriting film can manufacture the liquid crystal handwriting film with more abundant colors and various color changes.

Description

Method and equipment for manufacturing liquid crystal handwriting film

Technical Field

The invention relates to the technical field of liquid crystal handwriting films, in particular to a manufacturing method and manufacturing equipment of a liquid crystal handwriting film.

Background

In the prior art, the liquid crystal handwriting board is often manufactured by utilizing the characteristic that the cholesteric bistable liquid crystal can maintain the display without continuously supplying power. The Zizizi phase liquid crystal has two stable states of FC state and P state. When the cholesteric liquid crystal is in the FC state, the liquid crystal handwriting board is in a transparent state in appearance; when the cholesteric liquid crystal is in a P state under the action of pressure, light with a fixed wavelength can be reflected, so that the liquid crystal handwriting board can display handwriting. As the FC state and the P state of the cholesteric liquid crystal can be maintained for a long time without voltage, the energy consumption of the liquid crystal handwriting board is extremely low.

The existing liquid crystal handwriting film manufacturing method is to mix a cholesteric liquid crystal and glue by a liquid crystal filling device, fill the mixture between a top substrate and a bottom substrate with transparent electrode films, and then press the top substrate, the bottom substrate and the mixture of the cholesteric liquid crystal and the glue together to form the handwriting film. The current manufacturing method often pours liquid crystal materials capable of reflecting light rays of different wave bands into different positions of the handwriting film, so that different colors can be displayed in different areas of the same handwriting film. Although the liquid crystal handwriting board manufactured by the method can display a plurality of colors in the same handwriting board, only a single color can be fixedly displayed in the same area of the handwriting board, obvious block segmentation is formed between different colors, the change of the color is fixed and too single, and the color which can be presented by the handwriting board is very limited.

Disclosure of Invention

In view of the above, the present invention provides a method and an apparatus for manufacturing a liquid crystal handwriting pad, so as to solve the technical problems that the handwriting pad manufactured by the existing liquid crystal handwriting pad manufacturing technology has insufficient color and monotonous color change.

In a first aspect, the present invention provides a method for manufacturing a liquid crystal handwriting pad, comprising the steps of:

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 to obtain a mixed liquid crystal material mixed according to a preset mass percentage, wherein a first transparent electrode is arranged on the surface of the first substrate facing the second substrate, and a second transparent electrode is arranged on the surface of the second substrate facing the first substrate;

s30: and compounding the first substrate, the second substrate and the mixed liquid crystal material positioned between the first substrate and the second substrate into the liquid crystal handwriting film.

Preferably, the S20 further includes the steps of:

s211: mixing at least two liquid crystal materials with different central reflection wavelengths according to a preset mass percentage to obtain a mixed liquid crystal material;

s212: and pouring the mixed liquid crystal material between the first substrate and the second substrate.

Preferably, the S20 includes: and moving the filling ports for filling the liquid crystal materials with different central reflection wavelengths to the same filling position according to a preset time sequence for filling.

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

Preferably, the cholesteric liquid crystal comprises a first cholesteric liquid crystal and a second cholesteric liquid crystal, the first cholesteric liquid crystal having a central reflection wavelength of λ₁The central reflection wavelength of the second cholesteric liquid crystal is lambda₂Let d be | λ₁-λ₂|，d≥80nm。

Preferably, in the S212: when the mixed liquid crystal material is poured between the first substrate and the second substrate, the mass percentages of the liquid crystal materials with different central reflection wavelengths in the mixed liquid crystal material poured between the first substrate and the second substrate are randomly changed along with the position of the liquid crystal handwriting film.

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

Preferably, S40 is further included after S30, and the mixed liquid crystal material on the first substrate and the second substrate is cured using an external field to form polymer dispersed liquid crystal.

In a second aspect, the present invention provides an apparatus for manufacturing a liquid crystal writing film, comprising:

the liquid crystal material mixing and filling device is used for mixing at least two different types of liquid crystal materials and then filling the liquid crystal materials to the same position of the liquid crystal handwriting film or mixing the liquid crystal materials after filling the at least two different types of liquid crystal materials to the same position of the liquid crystal handwriting film;

the pressing device comprises a first pressing roller and a second pressing roller, the rotating 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 by a preset distance to press the liquid crystal handwriting film;

the pressing device is used for controlling the first pressing roller and the second pressing roller to rotate in opposite rotating directions to press the liquid crystal handwriting film after the liquid crystal material mixing and filling device fills the liquid crystal material.

Preferably, the rotation speed of the first press roller and the second press roller is 0.25 m/min-0.85 m/min.

Has the advantages that: the method and the equipment for manufacturing the liquid crystal handwriting film firstly 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 the mixed liquid crystal materials 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 materials into the liquid crystal handwriting film, so that the liquid crystal materials with a plurality of colors are mixed at the same position of the manufactured handwriting film, and the liquid crystal materials with different types act together at the same position to display the color which can not be displayed by a single liquid crystal material. When the proportion of various liquid crystal materials at different positions is different, the displayed colors are different, so that the liquid crystal handwriting film manufactured by the method and the equipment can display various colorful colors.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and for those skilled in the art, without any creative effort, other drawings can be obtained according to the drawings, and these drawings are all within the protection scope of the present invention.

FIG. 1 is a flowchart of a method for producing a liquid crystal handwriting film of embodiment 1 of the invention;

FIG. 2 is a flowchart of a method for compositely forming a liquid crystal handwriting film in embodiment 2 of the present invention;

FIG. 3 is a flowchart of a method for manufacturing a liquid crystal handwriting pad according to embodiment 2 of the invention;

FIG. 4 is a flowchart of a method for manufacturing a liquid crystal writing film including a curing process of a mixed liquid crystal material according to embodiment 2 of the present invention;

FIG. 5 is a schematic structural diagram of an apparatus for manufacturing a liquid crystal handwriting film according to the present invention;

FIG. 6 is a schematic structural diagram of a liquid crystal material filling apparatus according to the present invention;

FIG. 7 is a schematic structural diagram of a liquid crystal material filling apparatus with a valve according to the present invention;

FIG. 8 is a schematic structural diagram of a liquid crystal material filling apparatus with a first driving device according to the present invention;

FIG. 9 is a schematic structural view of an apparatus for manufacturing a liquid crystal handwriting film with a first driving device according to the present invention;

FIG. 10 is a schematic view of the present invention showing a structure of changing the position of the filling opening of the liquid crystal material by rotation;

FIG. 11 is a schematic structural diagram of an apparatus for manufacturing a liquid crystal writing film with an ultraviolet curing device according to the present invention;

FIG. 12 is a schematic structural view of a liquid crystal handwritten film manufacturing apparatus of a discharging device and a winding mechanism of the present invention;

fig. 13 is a schematic structural diagram of a handwriting film of the invention.

Parts and numbering in the drawings: the device comprises a first conducting layer 1, a second conducting layer 2, a liquid crystal layer 3, a transparent substrate layer 4, a ground color substrate layer 5, a laminating device 10, a first pressing roller 11, a second pressing roller 12, a laminating gap 13, a first substrate 21, a second substrate 22, a liquid crystal material pouring device 30, a conveying flow channel 31, a mixing flow channel 32, a liquid crystal material pouring port 33, a valve 34, a first driving device 35, an ultraviolet curing device 40, a first discharging device 50, a second discharging device 60 and a winding mechanism 70.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience in describing the present application and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. In case of conflict, the embodiments of the present invention and various features of the embodiments may be combined with each other within the scope of the present invention.

The liquid crystal writing board is generally composed of a shell material, a control circuit board and a writing film. The handwriting film is respectively a transparent film, a first layer of ITO transparent electrode, a liquid crystal layer, a first layer of ITO transparent electrode and a black bottom film from top to bottom. The liquid crystal layer contains cholesteric liquid crystal prepared from nematic liquid crystal and chiral agent.

The handwriting film can be made by filling a mixed monomer or prepolymer which can be polymerized under an external field (such as light, heat and the like), liquid crystal and a related liquid crystal composition (a liquid crystal material added with a chiral agent) between two base materials with conducting layers, wherein the components and the proportion of the liquid crystal composition can adjust the wave band of light reflected by the cholesteric liquid crystal.

The cholesteric liquid crystals are arranged in layers, and the molecules in the layers are parallel to each other. When the cholesteric liquid crystal is in a focal conic texture (FC) state, the molecular long axis of the cholesteric liquid crystal is vertical to the plane of the layers, and the directions of the molecular long axes of different layers are slightly changed; when the cholesteric liquid crystal is in a planar texture state (P state), the long axis of the molecules is parallel to the plane of the layer, and the long axes of the molecules of different layers are slightly changed, so that the long axes are arranged into a spiral structure along the normal direction of the layer. In the FC state, light rays directly pass through the liquid crystal layer and are absorbed by the black film at the lowest layer, and the complete black state is presented; when a finger or other hard objects press the liquid crystal film, the liquid crystal is extruded and overturned by pressure, the overturned area is in a P state, when natural light irradiates the overturned area of the liquid crystal layer, light with certain wavelength is reflected, and other colors are absorbed to form handwriting with corresponding colors; when a clear key on the handwriting board is pressed, the control circuit energizes the diaphragm, and the overturned area is stimulated by voltage to recover to an FC state. The FC state and the P state are the aforementioned bistable states, and the conversion between the FC state and the P state can be realized by the driving voltage.

Because different chiral agents and nematic liquid crystals can be mixed to prepare cholesteric liquid crystals reflecting light rays with different wavelengths, the cholesteric liquid crystals prepared by different chiral agents are filled in different areas of the same handwriting board in the prior art, so that each area divided by the handwriting board can display different colors. The liquid crystal handwriting film manufacturing method mixes a plurality of liquid crystal materials with different colors together and then pours the liquid crystal materials between two layers of base materials through a liquid crystal material pouring opening, so that the liquid crystal handwriting film capable of displaying rich colors is manufactured. The liquid crystal materials with different colors are liquid crystal materials which can reflect light with different colors after being made into the liquid crystal handwriting film. The liquid crystal material consists of a cholesteric liquid crystal capable of reflecting light of a specific waveband and an adhesive, and the color displayed after the liquid crystal material is prepared into a liquid crystal handwriting film is determined by the waveband of the light reflected by the liquid crystal material.

Example 1:

as shown in fig. 1, the present embodiment provides a method for manufacturing a liquid crystal handwriting pad, including the following steps:

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 to obtain a mixed liquid crystal material mixed according to a preset mass percentage, wherein a first transparent electrode is arranged on the surface of the first substrate facing the second substrate, and a second transparent electrode is arranged on the surface of the second substrate facing the first substrate; (ii) a

S30: the first substrate, the second substrate 22 and the mixed liquid crystal material poured between the first substrate and the second substrate are compounded into the liquid crystal handwriting film.

The liquid crystal material in S10 is prepared by mixing a cholesteric liquid crystal and an adhesive, wherein the cholesteric liquid crystal is prepared by mixing a nematic liquid crystal and a chiral agent for adjusting the central reflection wavelength of the cholesteric liquid crystal. The pitch of the cholesteric liquid crystal can be adjusted by controlling the type of the chiral agent and the content of the chiral agent, so that various cholesteric liquid crystals with different central reflection wavelengths can be prepared. The types of the chiral agents are defined by HTP values of the chiral agents, and different types of the chiral agents refer to the chiral agents with different HTP values. HTP is the twisting force constant of the chiral agent, and the pitch and the reflection wavelength can be varied by adjusting the chiral agent at different HTP values and the content in the liquid crystal material. A liquid crystal material prepared by mixing a single cholesteric liquid crystal with central reflection wavelength and an adhesive is 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 a handwriting film made of the liquid crystal material.

Wherein there are two kinds of realization methods with the liquid crystal material of multiple colours perfusing the same position of liquid crystal handwriting membrane, the first one is:

The second way of filling at least two liquid crystal materials with different central reflection wavelengths into the same position between the first substrate with the transparent electrode and the second substrate 22 is to move filling ports for filling liquid crystal materials with different colors to the same filling position range for filling;

for example, five colors of liquid crystal materials are provided, which are cholesteric liquid crystals with a central reflection wavelength of 400nm, the visual color is purple, and the code: violet; the cholesteric liquid crystal with the central reflection wavelength of 480nm has blue visual color and code number: blue; the cholesteric liquid crystal with the central reflection wavelength of 520nm has green visual color, code number: green; selecting cholesteric liquid crystal with central reflection wavelength of 580nm, wherein the visual color is yellow, and the code is as follows: yellow; cholesteric liquid crystal with central reflection wavelength of 620nm, orange visual color, code: orange; cholesteric liquid crystal with central reflection wavelength of 660nm, red visual color, code: and (3) red. Five liquid crystal material filling openings are correspondingly arranged. The corresponding relation between the five liquid crystal material filling ports and the filled liquid crystal color is as follows: the first liquid crystal material pouring opening is used for pouring purple liquid crystal materials, and the liquid crystal materials comprise: the second liquid crystal material pouring port is used for pouring blue liquid crystal materials, the third liquid crystal material pouring port is used for pouring green liquid crystal materials, the fourth liquid crystal material pouring port is used for pouring yellow liquid crystal materials, the fifth liquid crystal material pouring port is used for pouring red liquid crystal materials, and the five pouring ports are arranged in a row. The driving unit drives the liquid crystal material to fill and move along the arrangement direction port, so that the first liquid crystal material filling port moves to the filling position range for filling, then the second liquid crystal material filling port is driven to move to the filling position range for filling, and then the rest filling ports are moved to the same filling position range one by one according to the method for filling, so that the liquid crystal materials with different colors are distributed at the same position of the handwriting film. In this embodiment, after the first liquid crystal filling port is filled, the second liquid crystal filling port or any of the other liquid crystal filling ports may be moved to the same filling position range for filling. In this embodiment, the color type of the liquid crystal material for filling, the number of the liquid crystal material filling openings, the arrangement order of the liquid crystal material filling openings, and the filling order of the liquid crystal materials with different colors can be arbitrarily selected according to the production requirement, and are not limited herein.

After the liquid crystal materials with different central reflection wavelengths are mixed and coated on the handwriting film according to different proportions, the handwriting film can display various colors. The liquid crystal materials with different central reflection wavelengths can be mixed according to a preset proportion, and can also be mixed according to a random proportion, so that the proportion of various liquid crystal materials finally coated on the handwriting film is randomly changed along with the position of the handwriting film, namely, the mass percentage of the liquid crystal materials with different central reflection wavelengths in the liquid crystal mixed material filled between the first substrate and the second substrate 22 is randomly changed along with the position of the liquid crystal handwriting film, and the effect of randomly displaying rich colors and color change on the handwriting film is realized.

For example, a liquid crystal material which can exhibit red color when it acts alone and blue color when it acts alone are mixed together to obtain a mixed liquid crystal material. The mixed liquid crystal material is then poured between the first and second substrates 22. The handwriting film prepared in the way has the two liquid crystal materials coated at the same position, the two liquid crystal materials can display various colors between red and blue under the combined action, and the displayed colors are different due to different proportions of the two liquid crystal materials at different positions. If the mixing degree of the liquid crystal materials with the two colors is not controlled deliberately, the mixing proportion of the two materials at each position of the handwriting film is random, so the colors displayed by the manufactured handwriting film are also random, namely, the liquid crystal handwriting film manufactured by the equipment can display the effect of disordered colors. Although the foregoing examples only illustrate the mixing of liquid crystal materials of two colors, red and blue, it is understood that the present embodiment may also adopt any other liquid crystal materials of any color, and the number of mixed colors may be any number, and the types and the number of mixed colors are not limited here.

The first and second substrates 22 in S20 may be mylar PET, polyvinyl chloride PVC, polycarbonate PC, etc. compounded with transparent electrode films, and have a thickness of 45-265 μm. Transparent electrode layers are arranged on the first substrate and the second substrate. During pouring, the position of the pouring opening can be kept unchanged, so that the mixed liquid crystal material can be poured into a set area of the handwriting film, and the color change of the mixed liquid crystal materials can be displayed at different positions of the set area. Or after a mixed liquid crystal material is poured into a certain area of the liquid crystal handwriting film, the position of the pouring opening is moved, and other kinds of mixed liquid crystal materials are poured into the liquid crystal handwriting film, so that different combinations of color changes can be formed on the liquid crystal handwriting film.

When mixing, different conveying flow channels can be utilized to convey liquid crystal materials with different colors to the mixing flow channel, and then the mixed liquid crystal materials flow out from the mixing flow channel to be directly dripped onto the handwriting film. The liquid crystal materials with different colors are mixed in a flow channel mode, the liquid crystal materials can be mixed in the flowing process, the mixing and drip irrigation efficiency is high, the production efficiency can be obviously improved, the mixing degree randomness of the different materials is high during mixing in the flow channel process, and the liquid crystal handwriting film with randomly distributed colors can be manufactured.

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 the liquid crystal handwriting film.

The specific composite mode is that a first pressure facing the second substrate 22 is applied to the side of the first substrate away from the second substrate 22, and a second pressure facing the first substrate is applied to 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 by the first pressure and the second pressure to form the liquid crystal handwriting film. I.e. applying pressure on the outside of the two material layers, the first substrate, the second substrate 22 and the mixed liquid crystal material are pressed together by the rolling action.

Example 2

In order to ensure the composite effect, the first substrate and the second substrate 22 filled with the mixed liquid crystal material are pressed together by the first pressing roller and the second pressing roller, 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 the mixed liquid crystal material are pressed together when passing through the pressing gap, the mixed liquid crystal material moves from top to bottom to the pressing gap, and the filling position of the liquid crystal material is located above the pressing gap.

During compounding, the first substrate and the second substrate 22 can be conveyed towards the direction of the pressing gap by using the conveying device, the pressing gap is gradually narrowed 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 attached by the pressure of the pressing roller in the process of entering the pressing gap, and the liquid crystal handwriting film with a stable structure is formed. As shown in fig. 2, the specific steps are as follows:

s31, the first and second substrates 22 are conveyed to the nip position,

s32, passing the first substrate and the second substrate 22 through the stitching gap to stitch the first substrate and the second substrate 22;

and S33, rolling the pressed liquid crystal handwriting film.

Wherein the nip pressure acting on the first and second substrates 22 ranges from 0.1MPA to 0.3MPA and the nip is from 0.05mm to 0.3 mm. .

As shown in fig. 3, in order to ensure that the mixed liquid crystal material can be poured into the predetermined position of the handwriting film, step S2111 is further included before S212: determining the position of the mixed liquid crystal material pouring outlet according to the position of the color displayed by the handwriting film; s2112: and moving the position of the mixed liquid crystal material pouring outlet to a preset pouring position.

In addition, the position of the mixed liquid crystal material pouring outlet can be randomly moved in the pouring position range along the direction parallel to the pressing gap. The position range of the pouring can be set according to the area where the color to be displayed by the liquid crystal handwriting film is located. In the filling process, the position of the mixed liquid crystal material filling outlet is randomly moved along the direction parallel to the pressing gap, so that the occupation ratios of different types of liquid crystal materials coated on the handwriting film are randomly distributed on the handwriting film, and various randomly-changed colors are displayed.

In addition, the direction of the mixed liquid crystal material is poured during pouring is the same as the moving direction of the first and second substrates 22 when they enter the pressing gap. Because the stitching gap gradually narrows along the conveying direction of the first substrate and the second substrate 22, the first substrate and the second substrate 22 are extruded by the stitching gap in the process of entering the stitching gap, and air remained among the first substrate, the second substrate 22 and the mixed liquid crystal is extruded out, so that the quality of the stitched liquid crystal material is ensured.

In addition, the color difference of the handwriting film can be controlled by controlling the rotating speed of the coating roller, the glue storage amount between the first pressing roller and the second pressing roller and the length of a mixing rubber tube for mixing liquid crystal materials with different colors in the compounding process. When the rotating speed of the first pressing roller and the second pressing roller is between 0.02m/min and 0.85m/min, the obtained handwriting film has the most abundant colors. When the glue storage amount is controlled to be 3 ml-10 ml, the obtained handwriting film is rich in color. For example, the liquid crystal handwriting film is made of two colors of liquid crystal materials, namely blue with the central reflection wavelength of 420nm and yellow with the central reflection wavelength of 580 nm. Wherein the length of the mixed rubber tube is 3cm, the rotating speed of the coating roll is 0.5m/min, the glue storage amount between the two rolls is about 5ml, better gradual change color can be obtained, and the color which can be distinguished by naked eyes gradually changes: gradually changing from 420nm to 480nm, then to 520nm, then to 550nm, and then to 580 nm.

As shown in FIG. 4, S40 is further included after S30 for curing the mixed liquid crystal material on the first and second substrates 22 using an external field to form polymer dispersed liquid crystal. Wherein the applied external field may be heat, ions, ultraviolet light, or the like. In this embodiment, the mixed liquid crystal material is preferably cured by using ultraviolet light, the adhesive in the liquid crystal material is an ultraviolet-curable optical adhesive, the illumination intensity of the ultraviolet curing during curing is 10mW/cm2, and the curing time is 6 minutes

Example 3

As shown in fig. 5, the present embodiment provides a liquid crystal writing film manufacturing apparatus, which includes a pressing 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 pressing gap 13 through which a first substrate 21, a second substrate 22 and a liquid crystal filling material pass is formed between the first pressing roller 11 and the second pressing roller 12, and the pressing device 10 is configured to press the first substrate 21, the second substrate 22 and the liquid crystal filling material together to form a liquid crystal writing film when they pass through the gap;

in the liquid crystal writing film manufacturing process, the related conveying mechanism conveys the first substrate 21 and the second substrate 22 toward the nip 13 of the laminating device 10. Wherein the first substrate 21 and the second substrate 22 may be a PET film or a PC film combined with a transparent electrode film. Meanwhile, the driving mechanism drives the first pressing roller 11 and the second pressing roller 12 to rotate in opposite directions, wherein the rotating shaft directions of the first pressing roller 11 and the second pressing roller 12 are both perpendicular to the conveying direction of the first substrate 21 and the second substrate 22 when conveyed to the pressing gap 13. The liquid crystal material pouring device pours the liquid crystal material between the first substrate 21 and the second substrate 22 while the first substrate 21 and the second substrate 22 move toward the nip gap 13. When the first substrate 21, the second substrate 22 and the liquid crystal material pass through the pressing 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 through the rolling action of the two pressing rollers, and the liquid crystal handwriting film with a stable structure is formed.

The liquid crystal material filling device 30 includes a liquid crystal material conveying unit, a liquid crystal material mixing unit and a liquid crystal material filling port 33, the liquid crystal material conveying unit is communicated with the liquid crystal material mixing unit, the liquid crystal material mixing unit is communicated with the liquid crystal material filling 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, the liquid crystal material mixing unit is configured to mix the at least two liquid crystal materials of different colors together, and the liquid crystal material filling port 33 is configured to fill the liquid crystal material mixed by the liquid crystal material mixing unit between the first substrate 21 and the second substrate 22.

The liquid crystal filling device in the present embodiment includes a liquid crystal material mixing unit added between the liquid crystal material feeding unit and the liquid crystal material filling opening 33. The type of the liquid crystal material to be mixed may be determined before the pouring, for example, the liquid crystal material capable of displaying red and the liquid crystal material capable of displaying blue may be mixed, and then the liquid crystal material capable of displaying red and the liquid crystal material capable of displaying blue may be fed into the liquid crystal material mixing unit by the liquid crystal material feeding unit. In the liquid crystal material mixing unit, a liquid crystal material that can display red and a liquid crystal material that can display blue are mixed together. Finally, the liquid crystal material filling port 33 fills the mixed liquid crystal material between the first substrate 21 and the second substrate 22. The handwriting film manufactured by the equipment can display various colors between the two colors because the two liquid crystal materials are coated at the same position, the proportion of the two liquid crystal materials at different positions is different, and the displayed colors are different. If the mixing degree of the liquid crystal materials with the two colors is not controlled deliberately, the mixing proportion of the two materials at each position of the handwriting film is random, so the colors displayed by the manufactured handwriting film are also random, namely, the liquid crystal handwriting film manufactured by the equipment can display the effect of disordered colors. Although the foregoing examples only illustrate the mixing of liquid crystal materials of two colors, red and blue, it is understood that the present embodiment may also adopt any other liquid crystal materials of any color, and the number of mixed colors may be any number, and the types and the number of mixed colors are not limited herein.

As shown in fig. 6 and 7, in the present embodiment, the liquid crystal material conveying unit includes a plurality of conveying flow channels 31, each conveying flow channel 31 is configured to correspondingly convey a liquid crystal material of one color to the liquid crystal material mixing unit, wherein the colors of the liquid crystal materials conveyed by at least two conveying flow channels 31 are different.

In order to be able to convey a plurality of liquid crystal materials of different colors, the liquid crystal material conveying unit of the present embodiment is in a form of a combination of a plurality of conveying flow channels 31, each conveying flow channel 31 fixedly conveys only one color of liquid crystal material, and the liquid crystal material of the same color can be conveyed by one conveying flow channel 31 or by a plurality of conveying flow channels 31.

For example, the liquid crystal material transporting unit includes four transporting flow paths of a first transporting flow path, a second transporting flow path, a third transporting flow path and a fourth transporting flow path. The liquid crystal material conveying unit needs to convey liquid crystal materials of four colors, wherein the first conveying flow channel conveys the liquid crystal material of a first color, the second conveying flow channel conveys the liquid crystal material of a second color, the third conveying flow channel conveys the liquid crystal material of a third color, and the fourth conveying flow channel conveys the liquid crystal material of a fourth color.

For another example, the liquid crystal material transporting unit includes four transporting flow paths 31, a first transporting flow path, a second transporting flow path, a third transporting flow path, and a fourth transporting flow path. The liquid crystal material conveying unit needs to convey liquid crystal materials of three colors, wherein the first conveying flow channel conveys the liquid crystal material of a first color, the second conveying flow channel conveys the liquid crystal material of the first color, the third conveying flow channel conveys the liquid crystal material of a second color, and the fourth conveying flow channel conveys the liquid crystal material of a third color.

For another example, the liquid crystal material transport unit includes four transport flow paths, a first transport flow path, a second transport flow path, a third transport flow path, and a fourth transport flow path. The liquid crystal material conveying unit needs to convey liquid crystal materials of two colors, wherein the first conveying flow channel conveys the liquid crystal material of a first color, the second conveying flow channel conveys the liquid crystal material of the first color, the third conveying flow channel conveys the liquid crystal material of a second color, and the fourth conveying flow channel conveys the liquid crystal material of the second color.

For another example, the liquid crystal material transport unit includes four transport flow paths, a first transport flow path, a second transport flow path, a third transport flow path, and a fourth transport flow path. The liquid crystal material conveying unit needs to convey liquid crystal materials of two colors, wherein the first conveying flow channel conveys the liquid crystal material of a first color, the second conveying flow channel conveys the liquid crystal material of the first color, the third conveying flow channel conveys the liquid crystal material of the first color, and the fourth conveying flow channel conveys the liquid crystal material of the second color.

Further, the liquid crystal material mixing unit of the present embodiment includes at least one mixing flow channel 32, and the mixing flow channel 32 is configured to communicate with the delivery flow channel 31 corresponding to the liquid crystal material to be mixed.

In this embodiment, the liquid crystal material mixing unit adopts the form of the mixing flow channel 32, so that the liquid crystal materials with different colors can be quickly mixed in the flow channel process, the production efficiency of the handwriting film manufacturing equipment is obviously improved, the randomness of the mixing proportion of the liquid crystal materials with various colors on the handwriting film is also improved, and the effect of the color disorder distribution of the liquid crystal handwriting film is further enhanced.

In other embodiments, the liquid crystal material mixing unit may also adopt other structures or components capable of mixing liquid crystal materials of different colors, for example, a structure or component having a containing cavity capable of containing liquid crystal materials of multiple colors communicating with a liquid crystal material conveying unit capable of conveying liquid crystal materials of multiple colors. Or a pipeline structure communicated with a liquid crystal material conveying unit capable of conveying a plurality of colors.

In the present embodiment, the mixing channels 32 are configured to communicate with the conveying channels 31 corresponding to the liquid crystal materials 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, and then the mixing channel 32 communicates with the conveying channel 31 for conveying the liquid crystal material of the first color, the conveying channel for conveying the liquid crystal material of the second color and the conveying channel for conveying the liquid crystal material of the third color.

The method of communicating the mixing channel 32 with the conveying channel 31 corresponding to the liquid crystal material to be mixed may be to directly communicate the corresponding conveying 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, 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 needs to mix the liquid crystal material of the second color and the liquid crystal material of the third color. The first mixing flow channel is communicated with the conveying flow channel 31 for conveying the liquid crystal material with the first color and the conveying flow channel 31 for conveying the liquid crystal material with the second color through pipelines, and the second mixing flow channel is directly communicated with the conveying flow channel 31 for conveying the liquid crystal material with the second color and the conveying flow channel 31 for conveying the liquid crystal material with the third color through pipelines. The pipe connected to the mixing channel 32 can be a three-way pipe, a four-way pipe, or other connecting pipes with any number of ports. Wherein, when the length of the mixing flow channel is between 0.1cm and 7cm, the handwriting film with rich colors can be obtained.

It is understood that the number of the liquid crystal mixing channels 32 of the conveying channels 31 and the distribution manner of the conveying channels 31 can be set according to the kind of liquid crystal material to be mixed, and the specific number is not limited herein.

In addition to the aforementioned way in which the mixing channel 32 communicates with the respective delivery channel 31, other communication means are provided in this embodiment.

Specifically, the liquid crystal material mixing unit includes at least one mixing flow channel 32, the mixing flow channel 32 is connected to the plurality of conveying flow channels 31 through an on-off control device, and the on-off control device is used for controlling the connection and disconnection between the mixing flow channel 32 and the conveying flow channels 31. The on-off control device is configured to control the mixing flow channel 32 to communicate with the conveying flow channel 31 corresponding to the liquid crystal material to be mixed and to be closed off from the remaining conveying flow channels 31.

As shown in fig. 7, in the present embodiment, each delivery channel 31 is connected to each mixing channel 32 in advance by an on-off control device, which may be a pipe with an on-off valve 34.

For example, the liquid crystal material mixing unit has two mixing channels 32, 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 flow path 32 and the second mixing flow path 32 may be connected to the transport flow path 31 for transporting the liquid crystal material of the first color, the transport flow path 31 for transporting the liquid crystal material of the second color, and the transport flow path 31 for transporting the liquid crystal material of the third color, respectively, in advance by an on-off control device.

When the liquid crystal materials mixed in the first mixing channel 32 are poured, the valve 34 between the first mixing channel 32 and the conveying channel 31 for conveying the liquid crystal materials of the first color is opened, so that the first mixing channel 32 is communicated with the conveying channel 31 for conveying the liquid crystal materials of the first color, and the valve 34 between the first mixing channel 32 and the conveying channel 31 for conveying the liquid crystal materials of the second color is opened, so that the first mixing channel 32 is communicated with the conveying channel 31 for conveying the liquid crystal materials of the second color, and the valve 34 between the first mixing channel 32 and the conveying channel 31 for conveying the liquid crystal materials of the third color is closed, so that only the liquid crystal materials of the first color and the liquid crystal materials of the second color can enter the first mixing channel 32 through the corresponding conveying channels to be mixed.

When the liquid crystal materials mixed in the second mixing flow channel 32 are poured, the valve 34 between the second mixing flow channel 32 and the conveying flow channel 31 for conveying the liquid crystal materials of the second color is opened, so that the second mixing flow channel 32 is communicated with the conveying flow channel 31 for conveying the liquid crystal materials of the second color, meanwhile, the valve 34 between the second mixing flow channel 32 and the conveying flow channel 31 for conveying the liquid crystal materials of the third color is opened, so that the second mixing flow channel 32 is communicated with the conveying flow channel 31 for conveying the liquid crystal materials of the third color, and the valve 34 between the first mixing flow channel 32 and the conveying flow channel 31 for conveying the liquid crystal materials of the first color is closed, so that only the liquid crystal materials of the second color and the liquid crystal materials of the third color can enter the second mixing flow channel 32 through the corresponding conveying channels to be mixed.

By adopting the scheme, when the type of the liquid crystal material to be mixed in the mixing flow channel 32 is changed, the connection mode of the original pipeline is not required to be changed, and more flexible production can be realized.

The valves 34 controlling the on-off between the flow passages can be ordinary valves 34, and the operator can open or close the valves 34 according to the production process to control the on-off of the valves 34.

In addition, in order to improve the automation degree, the valve 34 for controlling the on-off of each flow channel can also adopt an electric control valve 34 and configure a corresponding controller, such as a PLC, an industrial personal computer, an embedded control system and the like. The signal output end of the controller is connected with the control signal input end of each electric control valve 34, and the controller can generate control signals according to the process requirements to automatically control the on-off condition of each valve 34, so that the types of the liquid crystal materials entering each mixing flow channel 32 to be mixed are controlled.

In practice, each of the transport channels 31 may be connected to a source of liquid crystal material of a corresponding color. For example, different types of liquid crystal materials may be stored in different storage containers, and then each of the transport channels 31 may communicate with the corresponding storage container according to the color type of the liquid crystal material. In order to enable the liquid crystal material to be transferred to the mixing flow channel 32 through the transfer flow channel 31, a pump may be provided to pump the liquid crystal material.

In this embodiment, a first driving device 35 is further included, and the driving device is configured to drive the liquid crystal material filling opening 33 to move, so that an outlet of the liquid crystal material filling opening 33 from which the corresponding liquid crystal material is dropped is located at a set filling position.

In this embodiment, a filling 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 filled between two layers of materials through the filling head.

In other embodiments, a structure in which the liquid crystal material mixing unit and the liquid crystal material filling port 33 are integrated may be adopted, and the mixing channel 32 is used for mixing different types of liquid crystal materials and filling the mixed liquid crystal materials at the same time, in this way, one end of the mixing channel 32 is used for receiving different types of liquid crystal materials, and the other end of the mixing channel forms the liquid crystal material filling port 33 for filling the mixed liquid crystal materials.

Whichever form of the liquid crystal material pouring port 33 is employed, the position where the liquid crystal material is dripped from the liquid crystal material pouring device 30 is preferably a side where the first substrate 21 and the second substrate 22 of the two pressing rollers enter the nip 13.

As shown in fig. 8 and 9, in the present embodiment, the first driving device 35 is used to drive the liquid crystal material pouring opening 33 to move, so that the preset pouring opening for pouring the liquid crystal material after being mixed correspondingly is located at the correct pouring position. For example, the liquid crystal material filling device 30 is provided with a first filling opening, a second filling opening and a third filling opening, which are respectively used for filling the first mixed liquid crystal material, the second mixed liquid crystal material and the third mixed liquid crystal material. When the previous process requires to pour the second mixed liquid crystal material into the first substrate 21 and the second substrate 22, the first driving device 35 drives the second pouring port to move to a position right above the pressing gap 13, and then the second mixed liquid crystal material flows out from the second pouring port to a position between the first substrate 21 and the second substrate 22. The direction of the arrow in fig. 9 is the moving direction of the liquid crystal material pouring port 33.

Wherein liquid crystal material perfusion device 30 can set up one and pour into the mouth and also can set up a plurality of mouths of pouring into, when being provided with a plurality of mouths of pouring into, a plurality of mouths of pouring into can be arranged into a row along the direction parallel with pressfitting gap 13, and first drive arrangement 35 drives this row of mouth of pouring into and moves back and forth along the direction parallel with pressfitting gap 13 to make corresponding mouth of pouring into in a plurality of mouths of pouring into be located the position of pouring of settlement.

In this embodiment, a plurality of filling heads may be further provided, each filling head is communicated with one mixing flow channel 32, a filling opening is formed on the conveying filling head, the plurality of filling heads are arranged along the first direction, and the first driving device 35 is configured to drive the plurality of filling heads to move along the first direction, so that the corresponding filling heads move to the filling position. Wherein the first direction may be along a direction parallel to the nip 13.

The pouring opening can be moved along a straight line direction or can be rotated around a certain center. As shown in fig. 10, the plurality of infusion ports are arranged at different circumferential positions of the same circumference. The first driving device 35 drives the plurality of filling ports to rotate along the circumference, and moves the filling port corresponding to the mixed liquid crystal material to be filled to a preset filling position. The direction of the arrow in fig. 10 is the direction of rotation of the liquid crystal material pouring port 33.

The first driving device 35 can drive each pouring opening to move synchronously or drive each pouring opening to move independently.

In the present application, the first substrate 21 and the second substrate 22 may enter the nip 13 along a vertical direction, and may also enter the nip 13 along a horizontal direction.

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

In addition, as shown in fig. 11, the present embodiment further includes an ultraviolet curing device 40, and the external light generated by the ultraviolet curing device 40 is used to irradiate the curing glue in the liquid crystal material during the pressing process, so as to quickly cure the liquid crystal glue, which is helpful for quick forming of the liquid crystal handwriting film.

As shown in fig. 12, in order to enable the first substrate 21 and the second substrate to be well pressed, the present embodiment further provides a pressure control device, and the pressure control device 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 comprises a controller, a pressure sensor and a pressing roller spacing adjusting mechanism, wherein the controller controls the pressing roller spacing adjusting mechanism to adjust the size of the pressing gap 13 according to the pressure applied to the liquid crystal handwriting film by the first pressing roller 11 and the second pressing roller 12 detected by the pressure sensor, and when the detected pressure is smaller than the preset pressure, the controller controls the spacing adjusting 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, the total pressure of the pressing process is improved, and vice versa.

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 include a first discharging device 50 for winding and discharging the first substrate 21, a second discharging device 60 for winding and discharging the second substrate 22, and a winding mechanism 70 for winding and discharging the laminated liquid crystal writing film on the material inlet side of the press roller.

As another embodiment, the liquid crystal filling device includes a liquid crystal material conveying unit, a plurality of liquid crystal material filling ports, and a driving unit, wherein the liquid crystal material conveying unit is configured to convey liquid crystal materials of at least two different colors to the liquid crystal material filling ports, each liquid crystal material filling port corresponds to a liquid crystal material of one color, the colors of the liquid crystal materials corresponding to at least two liquid crystal material filling ports are different, and the driving unit is configured to drive the liquid crystal material filling ports to the filling position. In this embodiment, a plurality of liquid crystal material pouring openings may be provided, each for dripping liquid crystal material of one color.

In addition, still include speed control device, speed control device is used for controlling the rotational speed of first compression roller and second compression roller, can control the degree that different colours's liquid crystal material mixes through the rotational speed of controlling two compression rollers to control the abundant degree of hand-written membrane color.

In addition, the color difference of the handwriting film can be controlled by controlling the rotating speed of the coating roller, the glue storage amount between the first pressing roller and the second pressing roller and the length of a mixing rubber tube for mixing liquid crystal materials with different colors in the compounding process. When the rotating speed of the first pressing roller and the second pressing roller is between 0.02m/min and 0.85m/min, the obtained handwriting film has the most abundant colors. When the glue storage amount is controlled to be 3 ml-10 ml, the obtained handwriting film is rich in color. For example, the liquid crystal handwriting film is made of two colors of liquid crystal materials, namely blue with the central reflection wavelength of 420nm and yellow with the central reflection wavelength of 580 nm. Wherein the length of the mixed rubber tube is 3cm, the rotating speed of the coating roller is 0.5m/min, the glue storage amount between the two rollers is about 5ml, and better gradual color can be obtained. The color that the flesh eye can distinguish gradually becomes: gradually changing from 420nm wave band to 480nm wave band, then gradually changing to 520nm wave band, then gradually changing to 550nm wave band, and then gradually changing to 580nm wave band.

Example 4

As shown in fig. 13, this embodiment provides a handwriting film with a color that can be arbitrarily changed with position, which includes a first conductive layer 1, a second conductive layer 2, and a liquid crystal layer 3, where the first conductive layer 1 and the second conductive layer 2 are oppositely disposed, 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 includes cholesteric liquid crystal and an adhesive;

in at least a part of the area of the handwriting film, at least two different types of cholesteric liquid crystals are mixed in the same position of the liquid crystal layer 3, and at least the mass percentages of the two types of cholesteric liquid crystals change with the position of the handwriting film, and the central reflection wavelengths of the different cholesteric liquid crystals are different.

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 electrified, a certain voltage is generated between the first conductive layer 1 and the second conductive layer 2, so that an electric field with certain intensity can be formed between the first conductive layer 1 and the second conductive layer 2. The liquid crystal molecules in the liquid crystal layer 3 can be changed from the P state to the FC state by the electric field. Wherein 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 ultraviolet light curing adhesive.

Wherein at least two different types of cholesteric liquid crystals are mixed in the same location in the liquid crystal layer 3 in at least a part of the area of the handwriting film. The at least one part of the area may be only a part of the handwriting film, may also include all areas of the handwriting film, may be a continuous area, may also be a plurality of independent areas, may be specified according to specific application requirements, and is not limited herein.

In addition, the handwriting film in this embodiment may further include a transparent substrate layer 4 and a background substrate layer which are arranged relatively, the transparent base layer is located on one side of the first conducting layer 1 departing from the liquid crystal layer 3, and the background substrate layer is located on one side of the second conducting layer 2 departing from the liquid crystal layer 3. The transparent substrate layer 4 and the ground color substrate layer can be made of a PET film or a PC film. When the courage is brilliant in the FC attitude, light passes through transparent substrate layer 4, shines the primary color substrate layer behind first transparent electrode and the liquid crystal layer 3, and at this moment the user can only see the colour on primary color substrate layer, and light is absorbed by the primary color substrate layer when the primary color substrate layer is black, therefore the user sees black handwriting film. Besides black, the base substrate layer can be made of other color materials.

Different types of cholesteric liquid crystals in the application refer to cholesteric liquid crystals with different central reflection wavelengths, and a single chiral agent and a nematic liquid crystal are prepared according to a fixed proportion to form the cholesteric liquid crystals reflecting light with a certain wavelength, so that a handwriting film can display a single color. In this embodiment, a plurality of cholesteric liquid crystals which originally can only display one color are mixed at the same position of the handwriting film, so that the position can display a color effect of the combined action of the mixed cholesteric liquid crystals, and the color displayed at the position is related to the mass percentages of the cholesteric liquid crystals. With the continuous change of the mass percentage of various cholesteric liquid crystals, the color displayed by the handwriting film is also continuously changed, so that the color displayed by the handwriting film in the embodiment is far richer than the color displayed by the independent action of various cholesteric liquid crystals. In addition, in this embodiment, the mass percentages of the various cholesteric liquid crystals change with the position of the writing board, so that the user can see not only richer colors but also richer color changes in the same area of the writing board or on the whole writing board.

In this embodiment, two cholesteric liquid crystals are taken as an example to describe the handwriting film of the present application. In this embodiment, the cholesteric liquid crystal includes a first cholesteric liquid crystal and a second cholesteric liquid crystal;

the cholesteric liquid crystal comprises a first cholesteric liquid crystal with a central reflection wavelength range of 420-480 nm and a second cholesteric liquid crystal with a central reflection wavelength of 600 nm;

the first cholesteric liquid crystal comprises a nematic liquid crystal with delta n of 0.3, a first chiral agent S811 and a second chiral agent S5011, and the nematic liquid crystal, the first chiral agent S811 and the second chiral agent S5011 respectively account for 80-92% by mass, 17-19.9% by mass and 0.1-3% by mass;

the second cholesteric liquid crystal comprises a nematic liquid crystal with delta n being 0.3, a first chiral agent S811 and a third chiral agent S2011, and the nematic liquid crystal, the first chiral agent S811 and the third chiral agent S2011 respectively account for 80%, 11% and 9% in mass percentage.

For example, when the first cholesteric liquid crystal is acted alone, the handwriting film only shows yellow, and the corresponding central reflection wavelength is 580 nm; when the second cholesteric liquid crystal acts alone, the handwriting film only displays blue, the corresponding central reflection wavelength is 420nm, and when the first cholesteric liquid crystal and the second cholesteric liquid crystal are mixed at the same position of the handwriting film and act simultaneously, the handwriting film can display the color with the central reflection wavelength between 420nm and 580 nm. With the change of the mass percentage of the first cholesteric liquid crystal and the second cholesteric liquid crystal, the colors which can be displayed on the handwriting film are also changed continuously between the wave bands, so that various colors between yellow and blue are displayed.

The two different cholesteric liquid crystals in this embodiment may also be cholesteric liquid crystals exhibiting other colors when acting alone, such as a cholesteric liquid crystal exhibiting a green color and a cholesteric liquid crystal exhibiting a red color, or a cholesteric liquid crystal exhibiting a green color and a cholesteric liquid crystal exhibiting a blue color, and the specific type of cholesteric liquid crystal may be selected as desired, without limitation. For example, the blue band ranges from 420 to 480nm, the nematic liquid crystal has a Δ n of 0.3, the nematic liquid crystal ratio is 80% or more, the ratio of the chiral agent S811 can be selected from 17% to 19.9%, and the ratio of the chiral agent S5011 can be selected from 0.1% to 3%.

In this embodiment, a mode of mixing three different cholesteric liquid crystals at the same position is adopted to realize more color display and more color change.

In this embodiment, the Zi-phase liquid crystal includes a first Zi-phase liquid crystal, a second Zi-phase liquid crystal and a third Zi-phase liquid crystal;

the first cholesteric liquid crystal is a cholesteric liquid crystal with the central reflection wavelength of 480nm, so that the handwriting color of the handwriting board is blue, the nematic liquid crystal proportion of which delta n is 0.3 is 80%, the addition proportion of the chiral agent S811 is 19.6%, and the addition proportion of the chiral agent S5011 is 0.4%.

The second cholesteric liquid crystal is cholesteric liquid crystal with central reflection wavelength of 520nm, so that the handwriting color of the handwriting board is green, the nematic liquid crystal proportion of which delta n is 0.3 is 80%, the addition proportion of the chiral agent S811 is 19.85%, and the addition proportion of the chiral agent S5011 is 0.15%.

The third cholesteric liquid crystal is cholesteric liquid crystal with central reflection wavelength of 600nm, so that the handwriting color of the handwriting board is red, the nematic liquid crystal proportion of which delta n is 0.3 is 80%, the addition proportion of the chiral agent S811 is 11%, and the addition proportion of the chiral agent S2011 is 9%.

The first cholesteric liquid crystal enables a handwriting film to display blue cholesteric liquid crystal when acting alone, the second cholesteric liquid crystal enables the handwriting film to display green cholesteric liquid crystal when acting alone, and the third cholesteric liquid crystal enables the handwriting film to display red cholesteric liquid crystal when acting alone. When three cholesteric liquid crystals are mixed at the same position of the handwriting film and then act together, the color effect of the mixed three colors can be displayed. When the mass percentages of the three cholesteric liquid crystals are changed continuously, the color displayed by the handwriting film is changed continuously. The change modes of the three cholesteric liquid crystal mass percentages can be any two changes, the other one is kept unchanged, and the other three can be changed simultaneously. It will be appreciated that in other embodiments the types of cholesteric liquid crystals can be extended to any number, for example n, n being a natural number and n.gtoreq.2, where the mass percentage of any m cholesteric liquid crystals varies with position, m being a natural number and 2.gtoreq.m.gtoreq.n.

As a preferred embodiment, the cholesteric liquid crystal comprises a first cholesteric liquid crystal having a central reflection wavelength λ and a second cholesteric liquid crystal having a central reflection wavelength λ₁The second cholesteric phase crystal center reflection wavelength lambda₂Let d be | λ₁-λ₂L and d is more than or equal to 80 nm. When the central reflection wavelength between the two cholesteric liquid crystals meets the range, the color difference change of the handwriting film manufactured by the method is more abundant.

This embodiment explains a handwriting pad that can realize different color changing modes.

As an example, the mass percentages of the various cholesteric liquid crystals in this embodiment may vary in any direction of the handwriting film, as well as in some predetermined direction on the handwriting film. The color of the handwritten film may thus also change in a rich manner in the aforementioned predetermined direction.

The direction of change can be any linear direction or any curved direction. The direction of the curve can be changed along a broken line formed by straight lines in different directions, or along a direction formed by combining the straight lines and the curved lines in different directions.

Wherein the mass percentages of the various cholesteric liquid crystals can be varied in one predetermined direction or simultaneously in a plurality of different directions. The specific change mode can be set according to the actual situation, and the handwriting films with different color changes can be correspondingly formed by the change modes of different mass percentages of the cholesteric liquid crystals, so that the color changes of the handwriting films are more abundant.

In addition, the mass percentages of the various cholesteric liquid crystals in the embodiment can also be randomly changed along with the positions, so that the colors appearing at the positions of the handwriting film are random, and the colors seen by a user after touching the handwriting film with a hand or other tools are randomly changed, thereby realizing the effect of disordered colors. Compared with the mode that only one color is displayed in a fixed area in the prior art, the handwriting film of the embodiment has richer color change, and the interestingness of the handwriting board is remarkably improved.

In this embodiment, moreover, it is possible to use various forms of random variation, for example, the mass percentages of the various cholesteric liquid crystals vary randomly in one direction or simultaneously in a plurality of directions, or the directions of variation are also random. For example, in the multi-cholesteric liquid crystal, the type of cholesteric liquid crystal whose mass percentage varies with position is random, or the number of types of cholesteric liquid crystal whose mass percentage varies with position is random. This allows a color display on the writing pad that varies randomly in various ways.

In addition, the change in the mass percentages of the various cholesteric liquid crystals with position in this example can be either hopping or continuous.

The mass percentages of various cholesterol-phase liquid crystals adopt a continuous change mode to enable the handwriting board to display continuously changed colors, so that the displayed colors are most abundant. Wherein the mass percentage of the various cholesteric liquid crystals can be continuously changed according to the direction. A random continuous variation may also be used. For example, the rate of change of the continuous change in the mass percent of various cholesteric liquid crystals changes randomly with the handwriting film. This allows the handwriting board to display the richest colors and different colors to appear on the handwriting board in a randomly varying manner. The interest of the tablet is further increased.

Example 5

This embodiment provides an electronic writing device including a control circuit for applying 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, and the writing film described in embodiment 4 in which the color is arbitrarily changed depending on the position.

The electronic writing device of this embodiment is manufactured by using the handwriting film in the foregoing embodiment, when the cholesteric liquid crystal is in the FC state, the liquid crystal handwriting board is only to display the color of the black substrate layer from the appearance, the position of the handwriting film under the action of the pressure is converted from the FC state to the P state, and the handwriting film at the position reflects light of a certain waveband, so that the user can see lines or traces of corresponding colors. When the control circuit applies a voltage exceeding a certain threshold value to the first electrode layer and the second electrode layer, an electric field formed between the first electrode layer and the second electrode layer originally in a P-state cholesteric liquid crystal is converted into an FC-state liquid crystal, and color traces on the handwriting film are removed.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The method for manufacturing the liquid crystal handwriting film is characterized by comprising the following steps of:

s30: and compounding the first substrate, the second substrate and the mixed liquid crystal material positioned between the first substrate and the second substrate into a liquid crystal handwriting film.

2. The method for manufacturing a liquid crystal handwriting film according to claim 1, wherein said S20 further comprises the steps of:

3. The method for manufacturing a liquid crystal handwriting film according to claim 1, wherein said S20 comprises: and moving each filling port for filling liquid crystal materials with different central reflection wavelengths to the same filling position according to a preset time sequence for filling.

4. A method of making a liquid-crystalline handwriting film according to claim 1, characterized in that said liquid-crystalline material comprises a cholesteric liquid-crystal and a binder, said cholesteric liquid-crystal comprising a nematic liquid-crystal and a chiral agent for adjusting the central reflection wavelength of the cholesteric liquid-crystal.

5. A method of making a liquid-crystalline handwriting film according to claim 4, characterized in that said cholesteric liquid-crystal comprises a first cholesteric liquid-crystal having a central reflection wavelength λ and a second cholesteric liquid-crystal having a central reflection wavelength λ₁The central reflection wavelength of the second cholesteric liquid crystal is lambda₂Let d be | λ₁-λ₂|，d≥80nm。

6. The method for producing a liquid crystal handwriting film according to claim 2, wherein in said S212: when the mixed liquid crystal material is poured between the first substrate and the second substrate, the mass percentages of the liquid crystal materials with different central reflection wavelengths in the mixed liquid crystal material poured between the first substrate and the second substrate are randomly changed along with the position of the liquid crystal handwriting film.

7. The method of claim 1, wherein in step S211, the flow rate of the at least one liquid crystal material having the central reflection wavelength is reduced from a first predetermined flow rate to a second predetermined flow rate, wherein the first predetermined flow rate is greater than the second predetermined flow rate.

8. The method of claim 1, further comprising S40 curing the mixed liquid crystal material on the first and second substrates using an external field to form polymer dispersed liquid crystal after S30.

9. A liquid crystal handwriting film manufacturing apparatus for implementing the liquid crystal handwriting film manufacturing method of any one of claims 1 to 8, comprising:

the pressing device comprises a first pressing roller and a second pressing roller, the rotating axes of the first pressing roller and the second pressing roller are parallel, and the liquid crystal handwriting film is pressed between the first pressing roller and the second pressing roller at a preset interval;

10. The liquid crystal writing film manufacturing apparatus according to claim 9, wherein: the rotating speed of the first pressing roller and the second pressing roller is 0.25-0.85 m/min.