CN110491291B - Flexible display screen cover plate - Google Patents
Flexible display screen cover plate Download PDFInfo
- Publication number
- CN110491291B CN110491291B CN201910747269.9A CN201910747269A CN110491291B CN 110491291 B CN110491291 B CN 110491291B CN 201910747269 A CN201910747269 A CN 201910747269A CN 110491291 B CN110491291 B CN 110491291B
- Authority
- CN
- China
- Prior art keywords
- layer
- aromatic polyamide
- flexible display
- fingerprint
- hardness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
- C09D175/04—Polyurethanes
- C09D175/14—Polyurethanes having carbon-to-carbon unsaturated bonds
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/60—Additives non-macromolecular
- C09D7/61—Additives non-macromolecular inorganic
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
- G02B1/14—Protective coatings, e.g. hard coatings
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/133305—Flexible substrates, e.g. plastics, organic film
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
- G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
- G09F9/301—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements flexible foldable or roll-able electronic displays, e.g. thin LCD, OLED
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/34—Silicon-containing compounds
- C08K3/36—Silica
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L71/00—Compositions of polyethers obtained by reactions forming an ether link in the main chain; Compositions of derivatives of such polymers
- C08L71/02—Polyalkylene oxides
Abstract
The invention discloses a flexible display screen cover plate, and relates to the technical field of optical films. The flexible display screen cover of the invention comprises: a transparent aromatic polyamide substrate; a fingerprint-proof hard layer disposed on one side of the transparent aromatic polyamide substrate; a polarizing layer provided on the other side of the aromatic polyamide-based sheet with respect to the fingerprint hardness preventing layer; and a hardened layer provided on the other side of the polarizing layer opposite to the transparent aromatic polyamide substrate. According to the invention, the polarizing layer is directly prepared on the transparent aromatic polyamide substrate, so that the overall thickness of the flexible display screen cover plate is reduced, and the overall hardness of the flexible display screen cover plate is greatly improved.
Description
Technical Field
The invention belongs to the technical field of optical film display, and particularly relates to a flexible display screen cover plate.
Background
The flexible display screen cover plate is mainly formed by compounding a rigid glass substrate or a resin substrate and a functional layer. The glass display cover plate can not be bent, and does not accord with the development trend of foldable display devices, and compared with glass, a polyimide material with high surface hardness and high toughness becomes a preferred material for the flexible display cover plate, but needs a surface coating to improve the hardness. In the using process, the problems that the hardness of the polyimide serving as a substrate is insufficient and the whole thickness of the device is thicker are found. In addition, two polaroids are respectively attached to two sides of the substrate in the liquid crystal display module, and the cover plate with the polarization function is manufactured by bonding the optical glue and the upper polaroid, so that the overall thickness is thicker, and the rigidity of the cover plate is linearly reduced due to the existence of the flexible optical glue layer.
Disclosure of Invention
The invention aims to provide a flexible display screen cover plate, which is characterized in that an aromatic polyamide material is adopted to prepare a substrate and is combined with a fingerprint hardness preventing layer to successfully endow the flexible display screen cover plate with ultrahigh hardness and good bending performance, the surface of the cover plate has hydrophobic and oleophobic characteristics, and meanwhile, a polarizing layer is directly prepared on a transparent aromatic polyamide substrate, so that the overall thickness is reduced, and the overall hardness is greatly improved due to the fact that one soft optical adhesive layer is omitted.
In order to solve the technical problems, the invention is realized by the following technical scheme:
the invention is a flexible display screen cover plate, comprising:
a transparent aromatic polyamide substrate;
a multi-layer anti-fingerprint hard layer disposed on one side of the transparent aromatic polyamide substrate;
a polarizing layer provided on the other side of the aromatic polyamide-based sheet with respect to the fingerprint hardness preventing layer;
and a plurality of hardened layers provided on the other side of the polarizing layer opposite to the transparent aromatic polyamide substrate.
In one embodiment of the present invention, the flexible display cover further includes a compensation layer disposed between the polarizing layer and the hardening layer.
In an embodiment of the invention, the flexible display screen cover further includes an ink layer disposed on the other side of the hardened layer opposite to the polarizing layer.
In one embodiment of the present invention, the thickness of the aromatic polyamide-based sheet is 12 μm to 50 μm.
In one embodiment of the present invention, the polarizing layer is fixed on the aromatic polyamide substrate by coating.
In one embodiment of the invention, the thickness of the polarizing layer is 20 μm to 80 μm.
In one embodiment of the present invention, the composition of the fingerprint hardness preventing layer includes urethane acrylate, silica, and perfluoropolyether fingerprint preventing oil.
In one embodiment of the present invention, the thickness of the fingerprint proof hardness layer is 1 μm to 20 μm.
In one embodiment of the present invention, the composition of the hardened layer includes difunctional urethane acrylate, trifunctional urethane acrylate, and tetrafunctional urethane acrylate.
The present invention also provides an electronic device, comprising:
a display screen;
a flexible display cover mounted over and covering the display; the flexible display screen cover plate comprises a transparent aromatic polyamide substrate; a fingerprint-proof hard layer disposed on one side of the transparent aromatic polyamide substrate; a polarizing layer disposed on the other side of the aromatic polyamide-based sheet with respect to the fingerprint hardness preventing layer; a hardened layer disposed on the other side of the polarizing layer opposite to the transparent aromatic polyamide substrate.
The substrate is made of the aromatic polyamide material and combined with the anti-fingerprint hardness layer, so that the ultra-high hardness and the good bending performance of the cover plate 9H are successfully endowed, the number of times of bending can reach more than 20 ten thousand, and meanwhile, under the target of the high hardness and the good bending performance, the thickness of the substrate and the coating can be thinner, so that the whole thickness of the cover plate is thinner, the aesthetic requirement of the public is better met, the warping performance of the whole coating is ensured, and the subsequent processing is convenient. The fingerprint hardness preventing layer enables the dynamic friction coefficient of the surface of the cover plate to be reduced to be below 0.03, and the super-smooth characteristic, the hydrophobic and oleophobic characteristic and the friction resistance characteristic are successfully endowed to the surface of the cover plate. Under the advantages, the cover plate of the embodiment can perfectly replace glass, and becomes the preferred choice of the flexible display screen cover plate. Through directly coating PVA layer on aromatic polyamide material base plate, not only reduced whole thickness, simultaneously because lacked the soft optics glue film of one deck, holistic hardness has obtained very big degree promotion. Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an electronic device according to the present invention;
FIG. 2 is a schematic structural diagram of the cover plate of the flexible display screen of FIG. 1;
FIG. 3 is another schematic structural diagram of the cover plate of the flexible display screen of FIG. 1;
FIG. 4 is another schematic structural diagram of the cover plate of the flexible display screen of FIG. 1;
FIG. 5 is another schematic view of the flexible display cover of FIG. 1;
fig. 6 is a schematic structural view of the polarizing layer in fig. 4 and 5.
In the drawings, the components represented by the respective reference numerals are listed below:
the display screen comprises an electronic device 1, a shell 2, a circuit board 3, a display screen 4, a flexible display screen cover 5, a protective layer 6, a polysilazane layer 7, a transparent aromatic polyamide substrate 8, an ink layer 9, a fingerprint-proof hardness layer 10, a hardening layer 11, a polarizing layer 12, a compensation layer 13, a TAC layer 14 and a PVA layer 15.
Detailed Description
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, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it is to be understood that the terms "opening," "upper," "lower," "thickness," "top," "middle," "length," "inner," "peripheral," and the like are used in an orientation or positional relationship that is merely for convenience in describing and simplifying the description, and do not indicate or imply that the referenced component or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present invention.
Referring to fig. 1 to 6 together, the present invention provides an electronic device 1, where the electronic device 1 may be a smart phone, a tablet computer, or a smart wearable device, and the electronic device 1 includes a flexible display cover 5, a display 4, a circuit board 3, and a housing 2. Wherein the display screen 4 is mounted on the housing 2 to form a display surface of the electronic device 1. The display 4 is used as a front shell of the electronic device 1 and forms a closed space with the housing 2 for accommodating other electronic components of the electronic device 1. Meanwhile, the display screen 4 forms a display surface of the electronic apparatus 1 for displaying information such as images, texts, and the like. The circuit board 3 is installed inside the housing 2 to accommodate the circuit board 3 in the above-mentioned closed space, and functional components such as a camera, a processor, a sensor and the like can be integrated on the circuit board 3, and meanwhile, the circuit board 3 is electrically connected with the display screen 4. A flexible display cover 5 is mounted to the display 4 to cover the display 4.
The flexible display cover 5 may be made of polyimide (CPI) instead of glass as a substrate, so that the screen becomes bendable and the hard screen becomes a soft screen. The manufacturing method of the flexible display screen cover plate 5 comprises the following steps: optical glass is used as a carrier plate, optical high-dimensional stability polyimide slurry can be coated on the optical glass through a slit type coating head, and then the optical high-dimensional stability polyimide slurry is solidified into a film under the protection of nitrogen to manufacture a flexible optical substrate; the water-oxygen barrier layer can be formed by depositing multiple layers of silicon-oxygen group and germanium-oxygen group-containing compounds such as SiO2(ii) a After the water-oxygen barrier layer is manufactured, manufacturing a functional layer of the display module by means of high-temperature evaporation and the like; a water-oxygen barrier layer is manufactured on the functional layer, and a layer of water-oxygen barrier film can be manufactured outside the water-oxygen barrier layer, so that the water-oxygen barrier effect is further enhanced; the carrier can be held by laser or the likeAnd separating the plate optical glass to manufacture the flexible display screen cover plate 5.
The flexible display cover 5 made of a polyimide substrate and a polymer coating layer containing a silicon oxide group and a germanium oxide group has the following problems: firstly, the hardness is not enough and can only reach 7H but can not reach 9H of the glass, so that the glass cannot be really replaced, if the hardness is increased by increasing the thickness of the coating, the warping and even curling can be caused, and the later process cannot be carried out; secondly, the thickness of the flexible display screen is thicker, in order to ensure the hardness, the thickness of the polyimide substrate is 50-80 μm, and the thickness of the hardened coating is more than or equal to 10 μm, so that the thickness of the flexible display screen is thicker, the overall thickness of the obtained device is thicker, and the overall design of the device is limited; thirdly, except for silicon oxygen groups, germanium oxygen groups are introduced to adjust the hardness of the material, and the addition of the germanium oxygen groups can affect the bending performance of the coating; although the water and oxygen blocking layer is manufactured on the polyimide substrate, the blocking rate of the whole device to water and oxygen is still low, and when water vapor or oxygen enters the device, the function of an internal functional layer is affected.
The flexible display screen cover plate 5 can also adopt a transparent aromatic polyamide material as a substrate of the flexible display screen cover plate 5 and a coating is arranged on the substrate, so that the hardness and the bending resistance of the traditional flexible display screen cover plate 5 are improved, and meanwhile, the penetration of components such as water, oxygen and the like is prevented.
Referring to fig. 1 and fig. 2 together, the present invention provides a flexible display panel cover 5, including: a transparent aromatic polyamide substrate 8, a multilayer polysilazane layer 7, a multilayer protective layer 6, and a multilayer ink layer 9.
Referring to fig. 1 and 2, the transparent aromatic polyamide substrate 8, the aromatic polyamide film is a polymer material having a main chain containing benzene rings and amide bonds (-CO-NH-), and is formed by condensation polymerization of aromatic para-dicarboxylic acid and aromatic para-diamine, and has a high young's modulus, in this embodiment, the young's modulus of the transparent aromatic polyamide substrate 8 is not less than 8GPa, because the young's modulus is too small to satisfy the requirement of hardness and the effect of hard to resist external impact, and the transparent aromatic polyamide substrate can be bent for multiple times, for example, 100 ten thousand times. The Young's modulus of the transparent aromatic polyamide substrate 8 in this example can be measured by a tensile method using a DHR-2 rheometer at, for example, 25 ℃ at room temperature and 1 Hz. The bend test method in this example is to mount the sample in a dynamic folding apparatus having two folding stages that rotate from, for example, 180 degrees (i.e., the sample is not bent) to, for example, 0 degrees (i.e., the sample is folded), and perform, for example, 100,000 cycles at a test rate of, for example, 6 cycles/minute and determine a 3mm bend radius from the gap between the two rigid plates in the closed state (i.e., 0 degrees).
The aromatic polyamide also has the characteristic of high hardness, for example, when the thickness of the transparent aromatic polyamide substrate 8 is 25 micrometers, the corresponding hardness can reach 4H, and when the thickness of the polyimide substrate is more than 80 micrometers, the hardness can reach 4H, so that the thickness of the cover plate can be greatly reduced by adopting the aromatic polyamide material to manufacture the substrate, and the aesthetic requirement of the public is better met. In the present embodiment, the thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 50 μm, if the thickness is less than 12 μm, the young's modulus is too small to satisfy the requirements of hardness and impact resistance, and if the thickness is more than 50 μm, the product cannot be mass-produced and the cost increase is too large), and in other embodiments, the thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 25 μm because the mass production is temporarily impossible at the present stage when the thickness is more than 25 μm. In addition, since benzene rings are present in the main chain of the aromatic polyamide molecule, the substrate prepared therefrom has excellent pressure tightness and thermal stability.
Referring to fig. 1 and 2, the polysilazane layer 7 is disposed on one side of the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is advantageous for increasing the hardness. The polysilazane layer 7 includes an organic polysilazane and an inorganic polysilazane, and the polysilazane layer 7 can be prepared on the transparent aromatic polyamide substrate 8 by spray coating, slit coating, or gravure coating. In this embodiment, the polysilazane layer 7 is prepared by slit coating, and the polysilazane liquid film is extrusion-coated on the moving transparent aromatic polyamide substrate 8 by the slit coating head to produce the polysilazane layer 7 with a certain thickness covered on the surface, wherein the film thickness can be obtained by calculating the liquid flow rate and the substrate moving speed, and the method has the advantages of high film uniformity, wide applicable coating viscosity range, high coating speed, and capability of producing a large-area film. In this embodiment, the polysilazane layer 7 is coated to a thickness of, for example, 1 μm to 20 μm, and then the polysilazane layer 7 is dried by using an oven, in this embodiment, a temperature range is set in the drying process to, for example, 50 ℃ to 200 ℃, in this embodiment, to, for example, 100/120/150/150/100 ℃, a residence time of each oven is 0.1min to 1min, a vehicle speed may be 5m/min to 20m/min, for example, 10m/min, and after the polysilazane layer 7 is prepared, a hardness may, for example, be greater than or equal to 8H, and may generally reach 9H.
Referring to fig. 1 and 2 together, the prepared polysilazane layer 7 is reactive to water and oxygen due to its active Si-H bonds and N-H bonds, and can be converted into a high-hardness transparent silicon oxynitride or silicon dioxide material under mild conditions, in this embodiment, the thickness of the prepared polysilazane layer 7 is, for example, 1 μm to 20 μm, if the thickness is less than 1 μm, the young's modulus is too small to satisfy the hardness and impact resistance requirements, if the thickness is more than 20 μm, cracks may occur in the bending experiment, in other embodiments, the thickness of the polysilazane layer 7 may be thinner, for example, 2 μm to 5 μm, which can satisfy the hardness and bending requirements at the same time and save the cost, but the hardness of the corresponding polysilazane layer 7 is not less than 7H, different hardness values can also be achieved by making different thicknesses in other embodiments. In addition, because the N-H bond in the structure of the polysilazane layer 7 is easy to be combined with the polar substrate, the adhesion force is high, in the embodiment, the N-H bond in the polysilazane layer 7 is combined with the N-H bond of the transparent aromatic polyamide substrate 8, so that the polysilazane layer 7 and the transparent aromatic polyamide substrate 8 have very strong adhesion force, and therefore, the dense coating formed by the polysilazane has very high wear resistance and hardness, and meanwhile, the polysilazane also has better flexibility, so that the requirements of the flexible display screen cover plate 5 are well met.
Referring to fig. 1 and fig. 2, the protection layer 6 is disposed on a side of the polysilazane layer 7 opposite to the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is beneficial to enhancing the protection effect. The protective layer 6 in this embodiment is a paint which can be applied very thinly to various substrates and can achieve excellent surface characteristics such as water and oil repellency, fingerprint adherence resistance, easy wiping, non-tackiness, and the like. The protective layer 6 in this embodiment contains a reactive silane group and a fluorine-modified organic group, and may be applied to the surface of the polysilazane layer 7 by spray coating, slit coating, or gravure roll coating, and the coating thickness may be, for example, 2nm to 100 nm. In this embodiment, the coating is performed by slit coating, the coating thickness is, for example, 8nm to 10nm, and then the coating is dried by an oven, wherein a step temperature range used in the drying process may be 50 ℃ to 200 ℃, for example, 60/80/120/140/100 ℃, the residence time of each oven may be 0.1min to 1min, for example, 0.6min, and the vehicle speed may be 5m/min to 20m/min, for example, 10 m/min. In other embodiments, other types of protective coatings may be applied to the polysilazane layer 7.
Referring to fig. 1 and fig. 2, the comparison of the characteristic parameters of the surface of the protection layer 6 and the characteristic parameters of the surface of the polysilazane layer 7 without the protection layer 6 is shown in the following table:
| measurement items | Unit of | Surface of the |
The surface of the |
| Water contact angle | ° | 117 | <10 |
| Roll off angle of hexadecane | ° | 6 | >45 |
| Abrasion resistance | ° | 108 | <10 |
| Coefficient of dynamic friction | 0.03 | 0.57 | |
| Hardness of | 9H | 8H |
The water contact angle measurement in this example is: mu.l of the measurement liquid is dropped on the film to be measured, and the contact angle of water after dropping for 5 seconds is measured using, for example, an automatic contact angle meter, and the angle is calculated by the θ/2 method. The dynamic friction coefficient in the present embodiment is measured using a friction coefficient meter, for example, according to astm d 1894.
As can be seen from the above table, under the protection of the protective layer 6, the surface characteristics of the flexible display panel cover 5 are significantly improved in terms of water contact angle, roll-off angle of hexadecane, abrasion resistance, dynamic friction coefficient and hardness, compared to the surface characteristics of the polysilazane layer 7 without the protective layer 6.
Referring to fig. 1 and 2, the ink layer 9 is disposed on the other side of the transparent aromatic polyamide substrate 8 opposite to the polysilazane layer 7, and the ink layer 9 divides the flexible display cover 5 into a visible region and a non-visible region, which can be set in multiple layers and in different colors. The ink layer 9 includes a main resin, a pigment and an auxiliary agent, wherein the main resin is composed of one or more of polyester, polyacrylate and polyurethane, in this embodiment, a shading effect is achieved by adding inorganic fillers such as carbon black, in other embodiments, other pigments and auxiliary agents such as white and color can also be added, and then, the printing of the display screen frame is completed by adopting a screen printing mode. The curing content of the ink used in this embodiment is, for example, 50%, the flash point is, for example, greater than 150 ℃, the printing mesh is, for example, 60 mesh to 250 mesh, the thickness of the printed ink layer 9 is, for example, 5 μm to 40 μm, if the thickness of the ink layer 9 is less than 5 μm, the effect of shielding light cannot be achieved, if the thickness of the ink layer 9 is greater than 40 μm, the step difference requiring optical glue filling is too large, in other embodiments, the thickness of the ink layer 9 may also be, for example, 8 μm to 25 μm, if the thickness of the ink layer 9 is greater than or equal to 8 μm, the optical density value is greater than or equal to 4, if the thickness of the ink layer 9 is greater than 25 μm, the step difference requiring optical glue filling is too large, at this time, the thickness of the optical glue is increased, and thus the overall hardness is rapidly reduced. Different thicknesses of the ink layer 9 can be obtained by using screen printing with different thicknesses and different mesh numbers. In addition, the optical density value of the ink layer 9 prepared in this embodiment is, for example, not less than 5, and the surface dyne value is, for example, not less than 32. In this embodiment, the dyne value may be obtained by drawing a line with a length of, for example, 5cm through the dyne stroke without shrinking within, for example, 5 s. After printing, the ink layer 9 is dried, for example, at a temperature of 150 ℃ for 10min to 20min in this embodiment, and the obtained ink layer 9 has good toughness.
Referring to fig. 1 and 2, in the present embodiment, the substrate made of the aromatic polyamide material and combined with the polysilazane coating layer successfully endows the cover plate 9H with the ultra-high hardness and the good bending performance, the number of times of bending can reach more than 20 ten thousand, and the thickness of the substrate and the coating layer can be made thinner under the target of the high hardness and the good bending performance, so that the overall thickness of the cover plate is thinner, the aesthetic requirement of the public is better met, the warping performance of the coated whole is ensured, and the subsequent process is facilitated. In this embodiment, the heights of four corners of the sample can be tested through the ruler, and the highest value is the warping value. Further, the dynamic friction coefficient of the surface of the cover plate is reduced to 0.03 or less by coating the protective layer 6, and the super-smooth property, the water-repellent oil-repellent property and the friction resistance property are successfully provided to the surface of the cover plate. Under the advantages, the cover plate can perfectly replace glass, and becomes the first choice of the flexible display screen cover plate.
Referring to fig. 1 and 3 together, another embodiment of the present invention further provides a flexible display cover 5, which includes a transparent aromatic polyamide substrate 8, a plurality of anti-fingerprint hard layers 10, a plurality of hardened layers 11, and a plurality of ink layers 9.
Referring to fig. 1 and 3, the aromatic polyamide material is used to fabricate the substrate of the flexible display cover 5 due to its excellent hardness and bending property. In this embodiment, the young's modulus of the transparent aromatic polyamide substrate 8 is, for example, not less than 8GPa, and the substrate can be bent several times, for example, 100 ten thousand times. The thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 50 μm in this embodiment, and the thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 25 μm in other embodiments.
Referring to fig. 1 and 3, the anti-fingerprint hard layer 10 is disposed on one side of the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is beneficial to increase the hardness and enhance the protection effect. The anti-fingerprint high-hardness layer mainly comprises a perfluoropolyether structure to improve the water contact angle of the hardness layer so as to achieve the anti-fouling effect. The hardness of the anti-fingerprint hardness layer 10 in this embodiment is, for example, not less than 7H, and the water contact angle is, for example, not less than 105 °. The coating thickness of the anti-fingerprint hard layer 10 in this embodiment is, for example, 1 μm to 20 μm, and the coating thickness of the anti-fingerprint hard layer 10 in other embodiments may be, for example, 3 μm to 8 μm, because if the coating thickness is too thin, the hardness of the anti-fingerprint hard layer 10 may not reach the target, if the coating thickness is too thick, warpage or curling may be caused, and if the coating thickness is too thick, cracks may be easily caused, thereby affecting flexibilityThe bending performance of the cover plate 5 of the display screen can not reach the target of bending not less than 20 ten thousand times. Preparing the anti-fingerprint hardness layer 10 on the transparent aromatic polyamide substrate 8 by spraying, slot coating or gravure roll coating, drying the anti-fingerprint hardness layer 10 coated on the substrate in an oven after the coating is finished, wherein the step temperature adopted for the drying in the embodiment is 20-100 ℃, for example 50/60/80/90/70 ℃, the speed range is 10-30 m/min, for example 20m/min, and the ultraviolet drying energy is not less than 300mJ/cm2。
The obtained anti-fingerprint hardness layers 10 with different component ratios and different thicknesses were tested for their performance to obtain the following table:
as can be seen from the above table: the fingerprint proof hard layer 10 is too thin, for example, 1 μm in thickness, at which the hardness is not satisfactory, and the fingerprint proof hard layer 10 is too thick, for example, 20 μm in thickness, at which cracks are easily generated at bending. When only the urethane acrylate and the perfluoropolyether anti-fingerprint oil are included in the components, and silica is not included, the hardness is low and is not satisfactory, when the silica is added in a small amount, for example, 5 parts by weight, the hardness is also not satisfactory, and when the silica is added in an excessive amount, for example, 30 parts by weight, the curling is serious. When the components only comprise polyurethane acrylate and silicon dioxide and no perfluoropolyether fingerprint-resistant oil is included, the water drop angle is small, and the water-and oil-resistant properties and the fingerprint-resistant adhesion properties are poor.
In the present example, the hardness was measured by a surface hardness tester and a pencil dedicated for pencil hardness measurement. The measurement load is 750g, the measurement speed is 30mm/min, the measurement distance is 5mm, the number of measurements is 5 times, and the hardness of a pencil whose pass number exceeds 4/5 is used as the evaluation result. The method for measuring the water drop angle in the present example is as follows: the measurement liquid 3 μ l was dropped on the anti-fingerprint hardness layer 10, and the water contact angle after dropping for 5 seconds, for example, was measured using an automatic contact angle meter, and the water drop angle was calculated by the θ/2 method.
The bending test method in the embodiment comprises the following steps: the sample is mounted in a dynamic folding apparatus having two folding stages that can rotate from 180 degrees (i.e., the sample is not bent) to 0 degrees (i.e., the sample is folded), in this example 100,000 cycles at a test rate of, for example, 6 cycles/minute. A 3mm bend radius is determined by the gap between the two rigid plates in the closed state (i.e., 0 degrees).
As shown in fig. 1 and 3, the hardened layer 11 is disposed on the other side surface of the transparent aromatic polyamide substrate 8. The hardened layer 11 comprises a two-to four-functional low-shrinkage urethane acrylate resin, and the hardened layer 11 is prepared on the other side surface of the transparent aromatic polyamide substrate 8 opposite to the fingerprint-resistant hard layer 10 by spraying, slit coating or gravure roll coating, in the embodiment, the thickness of the hardened layer 11 is, for example, 1 μm to 5 μm, because the hardened layer is too thin, the function of reinforcement cannot be achieved, and if the hardened layer is too thick, the whole bending effect is affected. The surface dyne value is, for example, not less than 40 because too small a dyne value affects the adhesion of the ink layer. After the coating is completed, the hardened layer 11 coated on the substrate is dried in an oven, in this embodiment, the step temperature for drying is 20-100 deg.C, such as 50/60/80/90/70 deg.C, the vehicle speed is 10-30 m/min, such as 20m/min, and the ultraviolet drying energy is not less than 300mJ/cm2。
Referring to fig. 1 and 3, the ink layer 9 is disposed on the other side surface of the hardened layer 11 opposite to the transparent aromatic polyamide substrate 8, and the ink layer 9 divides the flexible display cover 5 into a visible region and a non-visible region, which may be disposed in multiple layers and in different colors. The ink layer 9 includes a main resin, a pigment and an auxiliary agent, wherein the main resin is composed of one or more of polyester, polyacrylate and polyurethane, in this embodiment, a shading effect is achieved by adding inorganic fillers such as carbon black, and in other embodiments, other pigments and auxiliary agents such as white and color can be added, and then, the printing of the display screen frame is completed by adopting a screen printing mode. The ink used in this embodiment has a curing amount of, for example, 100%, a flash point of, for example, greater than 150, a printing mesh of, for example, 60 mesh to 250 mesh, and a thickness of, for example, 5 μm to 40 μm of the printed ink layer 9, and in other embodiments, the thickness of the ink layer 9 may also be, for example, 15 μm to 25 μm. Different thicknesses of the ink layer 9 can be obtained by using screen printing with different thicknesses and different mesh numbers. In addition, the optical density value of the ink layer 9 prepared in this embodiment is, for example, not less than 5, and the surface dyne value is, for example, not less than 32. After printing, the ink layer 9 is dried, for example, at a temperature of 150 ℃ for 10min to 20min, so that the obtained ink layer 9 has good toughness.
Referring to fig. 1 and 3, in the present embodiment, the substrate of the flexible display screen cover plate 5 is made of an aromatic polyamide material, and meanwhile, the anti-fingerprint hard layer 10 is prepared on one side of the substrate, and the hardened layer 11 is prepared on the other side of the substrate, so that the hardness of the cover plate is further improved by the two layers of coatings which are arranged oppositely, the ultra-high hardness and the bending resistance of the cover plate 9H are provided, the number of times of bending can reach more than 20 ten thousand, meanwhile, the hardness of the transparent aromatic polyamide substrate 8 can reach 4H when the thickness is 25 μm, and the hardness can reach 4H when the thickness of the polyimide substrate is more than 8 μm, so that the thickness of the cover plate can be greatly reduced by making the aromatic polyamide material, and the aesthetic requirement of the public can be met. In addition, the warping property of the processed coating is ensured by respectively preparing the coatings on the two sides of the transparent aromatic polyamide substrate 8, so that the subsequent processing is facilitated.
Referring to fig. 1 and 3, in the lcd module, two polarizers are respectively attached to two sides of the substrate, a lower polarizer is used for converting a light beam generated by the backlight source into polarized light, and an upper polarizer is used for analyzing the polarized light after being electrically modulated by the liquid crystal to generate a contrast between light and dark, thereby generating a display image. The imaging of the liquid crystal display module is required to depend on polarized light, any polaroid is omitted, and the liquid crystal display module cannot display images. The cover plate with the polarization function is formed by bonding the polyimide cover plate with the upper polarizer through optical cement, so that the overall thickness is thicker, and the rigidity of the cover plate is linearly reduced due to the existence of the flexible optical cement layer.
Referring to fig. 1, 4 and 6, another embodiment of the present invention further provides a flexible display cover 5, which is made of an aromatic polyamide substrate, wherein a polysilazane layer 7 and a protective layer 6 are respectively formed on one side of a transparent aromatic polyamide substrate 8, a polarizing layer and a printable hardened layer 11 are formed on the other side of the transparent aromatic polyamide substrate 8, and an ink layer 9 is formed on the hardened layer 11. The flexible display screen cover 5 of the present invention comprises: a transparent aromatic polyamide substrate 8, a multilayer polysilazane layer 7, a multilayer protective layer 6, a polarizing layer 12, a compensation layer 13, a multilayer cured layer 11, and a multilayer ink layer 9.
Referring to fig. 1, 4 and 6, the aromatic polyamide material is used to make the substrate of the flexible display cover 5 in the present invention due to its excellent hardness and bending property. In this embodiment, the young's modulus of the transparent aromatic polyamide substrate 8 is, for example, not less than 8GPa, and the substrate can be bent several times, for example, 100 ten thousand times. The thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 50 μm in this embodiment, and the thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 25 μm in other embodiments.
Referring to fig. 1, 4 and 6, the polysilazane layer 7 is formed on one side of the transparent aromatic polyamide substrate 8, and may be formed in multiple layers to improve hardness, and the polysilazane layer 7 is a novel polymer containing silicon, nitrogen and hydrogen, and has a structure in which Si-H bonds and N-H bonds are active and may react with moisture and polar surfaces to form a coating layer having a dense structure. The polysilazane layer 7 includes an organic polysilazane and an inorganic polysilazane, and in this embodiment, the polysilazane layer 7 is coated on the transparent aromatic polyamide substrate 8 by slit coating, for example, in a thickness of 1 μm to 20 μm, and the obtained polysilazane layer 7 has a hardness of, for example, not less than 7H, a water contact angle of the polysilazane layer 7 is not less than 105 °, and in other embodiments, a water contact angle of the polysilazane layer 7 is not less than 110 °. After coating, the polysilazane coating is dried in an oven at a stepped temperature set at, for example, 100/120/150/150/100 ℃ at a vehicle speed of, for example, 20m/min, and the overall hardness can reach, for example, 9H after coating.
Referring to fig. 1, 4 and 6, the protection layer 6 is disposed on a side of the polysilazane layer 7 opposite to the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is beneficial to improve the protection effect. The protective layer 6 in this embodiment is a paint which can be applied very thinly to various substrates and can achieve excellent surface characteristics such as water and oil repellency, fingerprint adherence resistance, easy wiping, non-tackiness, and the like. The protective layer 6 in this embodiment contains a reactive silane group and a fluorine-modified organic group, and may be applied to the surface of the polysilazane layer 7 by spray coating, slit coating, or gravure roll coating, and the coating thickness may be, for example, 2nm to 100 nm. In this embodiment, the coating is performed by slit coating, the coating thickness is, for example, 8nm to 10nm, and then the coating is dried by an oven, the step temperature used in the drying process is set to be 50 ℃ to 200 ℃, for example, 60/80/120/140/100 ℃, the time corresponding to each oven is 0.1min to 1min, for example, 0.6min, and the vehicle speed is 10m/min to 30m/min, for example, 20 m/min. In other embodiments, other types of protective coatings may be applied to the polysilazane layer 7. The comparison of the characteristic parameters of the surface of the protective layer 6 and the characteristic parameters of the surface of the polysilazane layer 7 without the protective layer 6 in this example is shown in table 1.
As shown in fig. 1, 4 and 6, the polarizing layer 12 is disposed on the other side of the transparent aromatic polyamide substrate 8 opposite to the polysilazane layer 7. The polarizing layer 12 is used to control the polarization direction of the light beam, and when natural light passes through the polarizing layer 12, light with the vibration direction perpendicular to the transmission axis of the polarizing layer 12 will be absorbed, and the transmitted light only remains polarized light with the vibration direction parallel to the transmission axis of the polarizing layer 12. In this embodiment, the polarizing layer 12 mainly includes a polyvinyl alcohol layer (i.e., a PVA layer 15) and triacetyl cellulose layers (i.e., TAC layers 14) respectively disposed on two sides of the polyvinyl alcohol layer, and in other embodiments, the polarizing layer 12 may be formed by compounding multiple layers, such as the PVA layer 15 in the middle, the TAC layers 14 on two sides, a pressure sensitive adhesive layer, a release layer, and the protective layer 6. The PVA layer 15 adsorbing the two-way absorption molecules is responsible for polarization, and determines key optical indexes such as polarization performance, light transmittance and color tone, the TAC layer 14 can protect the PVA layer 15 from being damaged by water vapor, ultraviolet rays and other external substances, and the environmental weather resistance of the polarizer is ensured. The polarizing layer 12 including the PVA layer 15 and the TAC layer 14 may be prepared on the transparent aromatic polyamide substrate 8 by spray coating, slit coating, or gravure roll coating, because the transparent aromatic polyamide substrate 8 has the characteristics of high modulus, bending resistance, bending radius equal to 3mm over 100 ten thousand times, excellent optical properties, and the like.
The PVA layer 15 and the TAC layer 14 may be combined by spraying, slot coating, or gravure roll coating. In this embodiment, the coating solids content is, for example, 40%, and the polarizing layer 12 is prepared to have a thickness of, for example, 20 μm to 80 μm, and in other embodiments the polarizing layer 12 may have a thickness of, for example, 20 μm to 60 μm. The coated polarizing layer 12 can be dried, cured and formed into a film by a 5-stage oven, and the drying step temperature can be set to 40 ℃/60 ℃/80 ℃/100 ℃/120 ℃/100 ℃.
As shown in fig. 1, fig. 4 and fig. 6, it is desirable for the polarizing layer 12 to completely block the external visible light spectrum, so as to achieve the effect of black integration. This requires the use of a polarization of sufficient polarization while incorporating the 1/4 λ material in the full visible spectrum, where λ is the wavelength of the light. In one embodiment of the invention, it is also possible to prepare a compensation layer 13 on the polarizing layer 12 on the side opposite to the transparent aromatic polyamide substrate 8, the polarizing layer 12 being compensated by a 1/4 λ material in the full visible spectrum, such as Polycarbonate (PC), cyclo-olefin polymer (COP) or a liquid crystal material. In the embodiment, the compensation layer 13 is made of the COP material, and the COP compensation layer 13 has low reflectivity and good integral black effect. In this embodiment, the compensation layer 13 may be prepared on the other side of the polarizing layer 12 opposite to the transparent aromatic polyamide substrate 8 by spray coating, slot coating or gravure roll coating, and the thickness of the compensation layer 13 in this embodiment is, for example, 20 μm to 80 μm, and the thickness of the compensation layer 13 in other embodiments may also be, for example, 20 μm to 40 μm.
As shown in fig. 1, 4 and 6, the hardening layer 11 is disposed on the other side of the polarizing layer 12 opposite to the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is advantageous for increasing the hardness. The hardened layer 11 comprises a two-to four-functional low-shrinkage urethane acrylate resin, and the hardened layer 11 is prepared on the other side of the transparent aromatic polyamide substrate 8 opposite to the anti-fingerprint hardness layer 10 by spraying, slot coating or gravure roll coating, wherein the thickness of the hardened layer 11 is, for example, 1 μm to 5 μm in the embodiment, and may also be, for example, 2 μm to 3 μm in other embodiments, and the surface dyne value is not less than 36 in the embodiment, and is not less than 40 in other embodiments. After the coating is completed, the hardened layer 11 coated on the substrate is dried in an oven, in this embodiment, the step temperature setting for drying is 50/60/80/90/70 ℃, the vehicle speed is 20m/min, for example, and the ultraviolet light drying energy is not less than 300mJ/cm, for example2。
Referring to fig. 1, 4 and 6, the ink layer 9 is disposed on the other side of the hardening layer 11 opposite to the polarizing layer 12, and the ink layer 9 divides the flexible display screen into a visible region and a non-visible region, which may be set in multiple layers and have different colors. The ink layer 9 includes a main resin, a pigment and an auxiliary agent, wherein the main resin is composed of one or more of polyester, polyacrylate and polyurethane, in this embodiment, a shading effect is achieved by adding inorganic fillers such as carbon black, and in other embodiments, other pigments and auxiliary agents such as white and color can be added, and then, the printing of the display screen frame is completed by adopting a screen printing mode. The ink used in this embodiment has a curing amount of, for example, 100%, a flash point of, for example, greater than 150, a printing mesh of, for example, 60 mesh to 250 mesh, and a thickness of, for example, 3 μm to 30 μm of the printed ink layer 9, and in other embodiments, the thickness of the ink layer 9 may also be, for example, 5 μm to 20 μm. Different thicknesses of the ink layer 9 can be obtained by using screen printing with different thicknesses and different mesh numbers. In addition, the optical density value of the ink layer 9 prepared in this embodiment is, for example, not less than 5, and the surface dyne value is, for example, not less than 32. After printing, the ink layer 9 is dried, for example, at a temperature of 150 ℃ for 10min to 20min, so that the obtained ink layer 9 has good toughness.
Referring to fig. 1, 4 and 6, in the present embodiment, the substrate made of the aromatic polyamide material and combined with the polysilazane coating successfully endows the cover plate 9H with the ultra-high hardness and the good bending performance, the number of times of bending can reach more than 20 ten thousand, and the thickness of the substrate and the coating can be made thinner under the target of the high hardness and the good bending performance, so that the overall thickness of the cover plate is thinner, the aesthetic requirement of the public is better met, the warping performance of the coating is ensured, and the subsequent process is facilitated. Further, the dynamic friction coefficient of the surface of the cover plate is reduced to 0.03 or less by coating the protective layer 6, and the super-smooth property, the water-repellent oil-repellent property and the friction resistance property are successfully provided to the surface of the cover plate. Under the advantages, the cover plate of the embodiment can perfectly replace glass, and becomes the preferred choice of the flexible display screen cover plate. By directly coating the PVA layer 15 on the transparent aromatic polyamide substrate 8, the whole thickness is reduced, and meanwhile, the whole hardness is improved to a great extent because one layer of soft optical adhesive layer is omitted.
Referring to fig. 1, 5 and 6, another embodiment of the present invention further provides a flexible display cover 5, which is manufactured by using an aromatic polyamide material as a substrate, preparing a fingerprint-proof hard layer 10 on one side of a transparent aromatic polyamide substrate 8, preparing a polarizing layer 12 and a printable hardened layer 11 on the other side of the transparent aromatic polyamide substrate 8, and finally preparing an ink layer 9 on the hardened layer 11. The flexible display screen cover 5 of the present invention comprises: the fingerprint-proof and anti-fingerprint hard ink comprises a transparent aromatic polyamide substrate 8, a multilayer fingerprint-proof hard layer 10, a polarizing layer 12, a compensation layer 13, a multilayer hardening layer 11 and a multilayer ink layer 9.
Referring to fig. 1, 5 and 6, the aromatic polyamide material is used to make the substrate of the flexible display cover 5 according to the present invention due to its excellent hardness and bending property. In this embodiment, the young's modulus of the transparent aromatic polyamide substrate 8 is, for example, not less than 8GPa, and the substrate can be bent several times, for example, 100 ten thousand times. The thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 50 μm in this embodiment, and the thickness of the transparent aromatic polyamide substrate 8 may be 12 μm to 25 μm in other embodiments.
Referring to fig. 1, 5 and 6, the anti-fingerprint hard layer 10 is disposed on one side of the transparent aromatic polyamide substrate 8, and the multiple layers are advantageous for improving the hardness and protecting the transparent aromatic polyamide substrate. The anti-fingerprint high-hardness layer comprises 100 parts by weight of main resin, 0-30 parts by weight of silicon dioxide and 0-0.1 part by weight of perfluoropolyether anti-fingerprint oil, wherein the main resin is polyurethane acrylate, the hardness and the wear resistance of the anti-fingerprint high-hardness layer are improved by adding inorganic silicon dioxide to realize organic-inorganic hybridization, and the water contact angle of the hardness layer is improved by adding the perfluoropolyether anti-fingerprint oil to achieve an anti-fouling effect. The hardness of the anti-fingerprint hardness layer 10 in this embodiment is, for example, not less than 7H, and the water contact angle is, for example, not less than 105 °. The coating thickness of the anti-fingerprint hard layer 10 in this embodiment is, for example, 1 μm to 20 μm, and the coating thickness of the anti-fingerprint hard layer 10 in other embodiments may also be, for example, 3 μm to 8 μm, because if the coating thickness is too thin, the hardness of the anti-fingerprint hard layer 10 may not reach the target, if the coating thickness is too thick, warpage or curling may be caused, and if the coating thickness is too thick, cracks may be easily caused, thereby affecting the bending performance of the flexible display panel cover 5, and may not reach the target of bending no less than 20 ten thousand times. Preparing the anti-fingerprint hardness layer 10 on the transparent aromatic polyamide substrate 8 by spraying, slot coating or gravure roll coating, drying the anti-fingerprint hardness layer 10 coated on the substrate in an oven after the coating is finished, wherein the step temperature for drying is 20-100 ℃, for example 50/60/80/90/70 ℃, the vehicle speed is 10m/min-30m/min, for example 20m/min, and the ultraviolet drying energy is not less than 300mJ/cm2。
The obtained anti-fingerprint hardness layers 10 with different component ratios and different thicknesses were tested for their performance to obtain the following table:
as can be seen from the above table: the fingerprint proof hard layer 10 is too thin, for example, 1 μm in thickness, at which the hardness is not satisfactory, and the fingerprint proof hard layer 10 is too thick, for example, 20 μm in thickness, at which cracks are easily generated at bending. When only the urethane acrylate and the perfluoropolyether anti-fingerprint oil are included in the components, and silica is not included, the hardness is low and is not satisfactory, when the silica is added in a small amount, for example, 5 parts by weight, the hardness is also not satisfactory, and when the silica is added in an excessive amount, for example, 30 parts by weight, the curling is serious. When the components only comprise polyurethane acrylate and silicon dioxide and no perfluoropolyether fingerprint-resistant oil is included, the water drop angle is small, and the water-and oil-resistant properties and the fingerprint-resistant adhesion properties are poor.
Referring to fig. 1, 5 and 6, a polarizing layer 12 is disposed on the other side surface of the transparent aromatic polyamide substrate 8 opposite to the anti-fingerprint hard layer 10. The polarizing layer 12 is used to control the polarization direction of the light beam, and when natural light passes through the polarizing layer 12, light with the vibration direction perpendicular to the transmission axis of the polarizing layer 12 will be absorbed, and the transmitted light only remains polarized light with the vibration direction parallel to the transmission axis of the polarizing layer 12. In this embodiment, the polarizing layer 12 mainly includes a polyvinyl alcohol layer (i.e., a PVA layer 15) and triacetyl cellulose layers (i.e., TAC layers 14) respectively disposed on two sides of the polyvinyl alcohol layer, and in other embodiments, the polarizing layer 12 may be formed by compounding multiple layers, such as the PVA layer 15 in the middle, the TAC layers 14 on two sides, a pressure sensitive adhesive layer, a release layer, and the protective layer 6. The PVA layer 15 adsorbing the two-way absorption molecules is responsible for polarization, and determines key optical indexes such as polarization performance, light transmittance and color tone, the TAC layer 14 can protect the PVA layer 15 from being damaged by water vapor, ultraviolet rays and other external substances, and the environmental weather resistance of the polarizer is ensured. The polarizing layer 12 including the PVA layer 15 and the TAC layer 14 may be prepared on the transparent aromatic polyamide substrate 8 by spray coating, slit coating, or gravure roll coating, because the transparent aromatic polyamide substrate 8 has the characteristics of high modulus, bending resistance, bending radius equal to 3mm over 100 ten thousand times, excellent optical properties, and the like.
The PVA layer 15 and the TAC layer 14 may be combined by spraying, slot coating, or gravure roll coating. In this embodiment, the coating solids content is, for example, 40%, and the polarizing layer 12 is prepared to have a thickness of, for example, 20 μm to 80 μm, and in other embodiments the polarizing layer 12 may have a thickness of, for example, 20 μm to 60 μm. The coated polarizing layer 12 may be dried and cured to form a film by, for example, a 5-stage oven, the drying step temperature may be 20 to 200 ℃, for example, 50/70/90/110/100 ℃, and the residence time of each stage of oven is 0.1min to 1min, for example, 0.6 min.
Referring to fig. 1, 5 and 6, it is desirable that the polarizing layer 12 completely block the visible spectrum, so as to achieve the effect of black integration. This requires the use of a polarization of sufficient polarization while incorporating the 1/4 λ material for the full visible spectrum, λ being the wavelength. In one embodiment of the invention, it is also possible to prepare a compensation layer 13 on the polarizing layer 12 on the side opposite to the transparent aromatic polyamide substrate 8, the polarizing layer 12 being compensated by a 1/4 λ material in the full visible spectrum, such as Polycarbonate (PC), cyclo-olefin polymer (COP) or a liquid crystal material. In the embodiment, the compensation layer 13 is made of the COP material, and the COP compensation layer 13 has low reflectivity and good integral black effect. In this embodiment, the compensation layer 13 may be prepared on the other side of the polarizing layer 12 opposite to the transparent aromatic polyamide substrate 8 by spray coating, slot coating or gravure roll coating, and the thickness of the compensation layer 13 in this embodiment is, for example, 20 μm to 80 μm, and the thickness of the compensation layer 13 in other embodiments may also be, for example, 20 μm to 40 μm.
As shown in fig. 1, 5 and 6, the hardening layer 11 is disposed on the other side of the polarizing layer 12 opposite to the transparent aromatic polyamide substrate 8, and may be disposed in multiple layers, which is advantageous for increasing the hardness. The hardened layer 11 comprises a two-to four-functional low-shrinkage urethane acrylate resin, and the hardened layer 11 is prepared on the other side surface of the transparent aromatic polyamide substrate 8 opposite to the fingerprint-proof hard layer 10 by spraying, slot coating or gravure roll coating, wherein the thickness of the hardened layer 11 is 1-5 μm in the embodiment, and the other side surface is a solid surfaceIn the embodiment, the surface dyne value may be, for example, 2 μm to 3 μm, which is not less than 36 in the embodiment, and is not less than 40 in other embodiments. After the coating is completed, the hardened layer 11 coated on the substrate is dried in an oven, and the step temperature used for drying in this embodiment may be 50 ℃ to 200 ℃, for example 50/60/80/90/70 ℃, the residence time of each oven may be 0.1min to 1min, for example 0.6min, and the vehicle speed may be 5m/min to 20m/min, for example 10 m/min. Ultraviolet drying energy of, for example, not less than 300mJ/cm2。
Referring to fig. 1, 5 and 6, the ink layer 9 is disposed on the other side of the hardening layer 11 opposite to the polarizing layer 12, and the ink layer 9 divides the flexible display screen into a visible region and a non-visible region, and may be disposed in multiple layers and have different colors. The ink layer 9 includes a main resin, a pigment and an auxiliary agent, wherein the main resin is composed of one or more of polyester, polyacrylate and polyurethane, in this embodiment, a shading effect is achieved by adding inorganic fillers such as carbon black, and in other embodiments, other pigments and auxiliary agents such as white and color can be added, and then, the printing of the display screen frame is completed by adopting a screen printing mode. The ink used in this embodiment has a curing amount of, for example, 100%, a flash point of, for example, greater than 150, a printing mesh of, for example, 60 mesh to 250 mesh, and a thickness of, for example, 3 μm to 30 μm of the printed ink layer 9, and in other embodiments, the thickness of the ink layer 9 may also be, for example, 5 μm to 20 μm. Different thicknesses of the ink layer 9 can be obtained by using screen printing with different thicknesses and different mesh numbers. In addition, the optical density value of the ink layer 9 prepared in this embodiment is, for example, not less than 5, and the surface dyne value is, for example, not less than 32. After printing, the ink layer 9 is dried, for example, at a temperature of 150 ℃ for 10min to 20min, so that the obtained ink layer 9 has good toughness.
Referring to fig. 1, 5 and 6, in the present embodiment, the substrate made of the aromatic polyamide material and the anti-fingerprint hard layer 10 are combined to successfully provide the cover plate 9H with the ultra-high hardness and the good bending performance, the number of times of bending can reach more than 20 ten thousand, and the thickness of the substrate and the coating can be made thinner under the target of the high hardness and the good bending performance, so that the overall thickness of the cover plate is thinner, the aesthetic requirement of the public is better met, the warping performance of the coating is ensured, and the subsequent process is facilitated. Further, the dynamic friction coefficient of the surface of the cover plate is reduced to 0.03 or less by coating the protective layer 6, and the super-smooth property, the water-repellent oil-repellent property and the friction resistance property are successfully provided to the surface of the cover plate. Under the advantages, the cover plate of the embodiment can perfectly replace glass, and becomes the preferred choice of the flexible display screen cover plate 5. Through directly coating PVA layer 15 on aromatic polyamide material base plate, not only reduced whole thickness, simultaneously because lacked the soft optics glue film of one deck, holistic hardness has obtained very big degree promotion.
Referring to fig. 1 to 6, the present invention uses a transparent aromatic polyamide material as a substrate of the flexible display cover 5 and a coating layer is disposed on the substrate, so as to improve the hardness and bending resistance of the conventional flexible display cover 5 and prevent the penetration of components such as water, oxygen, etc.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (8)
1. A flexible display screen cover plate, characterized in that it includes:
a transparent aromatic polyamide substrate;
a multi-layer anti-fingerprint hard layer disposed on one side of the transparent aromatic polyamide substrate;
a polarizing layer provided on the other side of the aromatic polyamide-based sheet with respect to the fingerprint hardness preventing layer;
a plurality of hardened layers provided on the other side of the polarizing layer opposite to the transparent aromatic polyamide substrate;
a compensation layer disposed between the polarizing layer and the hardening layer; the compensation layer is made of 1/4 lambda material with low reflectivity and good black integral effect and full visible spectrum;
wherein λ is a wavelength of light, and the 1/4 λ material of the full visible spectrum includes one of polycarbonate, cyclic olefin polymer, and liquid crystal material;
and the ink layer is arranged on the other side surface, opposite to the polarizing layer, of the hardening layer.
2. The flexible display cover sheet of claim 1, wherein the aromatic polyamide-based sheet has a thickness of 12 μm to 50 μm.
3. The flexible display panel cover according to claim 1, wherein the polarizing layer is fixed on the aromatic polyamide substrate by coating.
4. The cover sheet for a flexible display screen according to claim 1, wherein the polarizing layer has a thickness of 20 μm to 80 μm.
5. The flexible display screen cover according to claim 1, wherein the composition of the fingerprint hardness prevention layer comprises urethane acrylate, silica and perfluoropolyether fingerprint prevention oil.
6. The flexible display cover according to claim 1, wherein the anti-fingerprint hard layer has a thickness of 1 μm to 20 μm.
7. The cover sheet according to claim 1, wherein the hardened layer comprises di-functional polyurethane acrylate, tri-functional polyurethane acrylate, or tetra-functional polyurethane acrylate.
8. An electronic device, comprising:
a display screen;
a flexible display cover mounted over and covering the display; the flexible display screen cover plate comprises a transparent aromatic polyamide substrate; a fingerprint-proof hard layer disposed on one side of the transparent aromatic polyamide substrate; a polarizing layer disposed on the other side of the aromatic polyamide-based sheet with respect to the fingerprint hardness preventing layer; a hardened layer provided on the other side of the polarizing layer opposite to the transparent aromatic polyamide substrate; a compensation layer disposed between the polarizing layer and the hardening layer; the compensation layer is made of 1/4 lambda material with low reflectivity and good black integral effect and full visible spectrum; wherein λ is a wavelength of light, and the 1/4 λ material of the full visible spectrum includes one of polycarbonate, cyclic olefin polymer, and liquid crystal material; and the ink layer is arranged on the other side surface of the hardening layer relative to the polarizing layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910747269.9A CN110491291B (en) | 2019-08-14 | 2019-08-14 | Flexible display screen cover plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910747269.9A CN110491291B (en) | 2019-08-14 | 2019-08-14 | Flexible display screen cover plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110491291A CN110491291A (en) | 2019-11-22 |
| CN110491291B true CN110491291B (en) | 2022-01-11 |
Family
ID=68550927
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910747269.9A Active CN110491291B (en) | 2019-08-14 | 2019-08-14 | Flexible display screen cover plate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110491291B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113640910B (en) * | 2021-07-12 | 2024-02-02 | 安徽菲尔慕材料有限公司 | Polyimide hardening film with polarizing function and manufacturing process thereof |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790060A (en) * | 2004-12-17 | 2006-06-21 | 日东电工株式会社 | Hard-coated film and method of manufacturing the same |
| CN101204697A (en) * | 2006-12-18 | 2008-06-25 | 日东电工株式会社 | Production method of hard coating thin film, hard coating thin film, polarizing disc and image display apparatus |
| CN103540183A (en) * | 2013-10-27 | 2014-01-29 | 合肥乐凯科技产业有限公司 | Anti-fingerprint transparent hardening film for touch screen |
| CN206892367U (en) * | 2017-04-28 | 2018-01-16 | 新恒东薄膜材料（常州）有限公司 | A kind of UV hardens SRF films |
| CN108882598A (en) * | 2018-09-03 | 2018-11-23 | 维达力实业(深圳)有限公司 | Composite decking and preparation method thereof |
| CN108922406A (en) * | 2018-08-22 | 2018-11-30 | 京东方科技集团股份有限公司 | A kind of flexible cover plate, organic display panel, display device and production method |
| CN109747235A (en) * | 2017-11-07 | 2019-05-14 | 财团法人工业技术研究院 | Protect structure and electronic device |
| CN109940948A (en) * | 2019-03-29 | 2019-06-28 | 京东方科技集团股份有限公司 | A kind of preparation method of flexible cover plate, display device and flexible cover plate |
| CN109981847A (en) * | 2019-03-26 | 2019-07-05 | Oppo广东移动通信有限公司 | Electronic equipment, glass cover-plate and its manufacturing method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10751980B2 (en) * | 2016-06-24 | 2020-08-25 | Toray Industries, Inc. | Multilayer film |
| CN207817243U (en) * | 2017-12-27 | 2018-09-04 | 深圳市盛波光电科技有限公司 | Polaroid and flexible display screen |
| CN109885210A (en) * | 2019-03-25 | 2019-06-14 | 维达力实业(深圳)有限公司 | The preparation method of composite decking and composite decking |
-
2019
- 2019-08-14 CN CN201910747269.9A patent/CN110491291B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790060A (en) * | 2004-12-17 | 2006-06-21 | 日东电工株式会社 | Hard-coated film and method of manufacturing the same |
| CN101204697A (en) * | 2006-12-18 | 2008-06-25 | 日东电工株式会社 | Production method of hard coating thin film, hard coating thin film, polarizing disc and image display apparatus |
| CN103540183A (en) * | 2013-10-27 | 2014-01-29 | 合肥乐凯科技产业有限公司 | Anti-fingerprint transparent hardening film for touch screen |
| CN206892367U (en) * | 2017-04-28 | 2018-01-16 | 新恒东薄膜材料（常州）有限公司 | A kind of UV hardens SRF films |
| CN109747235A (en) * | 2017-11-07 | 2019-05-14 | 财团法人工业技术研究院 | Protect structure and electronic device |
| CN108922406A (en) * | 2018-08-22 | 2018-11-30 | 京东方科技集团股份有限公司 | A kind of flexible cover plate, organic display panel, display device and production method |
| CN108882598A (en) * | 2018-09-03 | 2018-11-23 | 维达力实业(深圳)有限公司 | Composite decking and preparation method thereof |
| CN109981847A (en) * | 2019-03-26 | 2019-07-05 | Oppo广东移动通信有限公司 | Electronic equipment, glass cover-plate and its manufacturing method |
| CN109940948A (en) * | 2019-03-29 | 2019-06-28 | 京东方科技集团股份有限公司 | A kind of preparation method of flexible cover plate, display device and flexible cover plate |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110491291A (en) | 2019-11-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110473471B (en) | Flexible display screen cover plate | |
| US8415003B2 (en) | Flexible substrate for display panel and manufacturing method thereof | |
| CN107545847A (en) | Display device | |
| KR102096330B1 (en) | Optical multilayer body | |
| US9188807B2 (en) | Hard-screen polarizing plate for liquid crystal screen | |
| CN110576664A (en) | Flexible display screen cover plate | |
| JP6936206B2 (en) | Optical laminate | |
| CN109964156A (en) | Window substrate manufactures its method and the image display comprising it | |
| CN110491291B (en) | Flexible display screen cover plate | |
| CN110602274B (en) | Flexible display screen cover plate | |
| CN112592507B (en) | Hard coat film, and window and image display device comprising same | |
| CN113703075B (en) | Display module and display device | |
| US20210384476A1 (en) | Electronic device and method of fabricating the same | |
| CN110531897A (en) | Cover plate assembly, preparation method, touch panel and display device | |
| CN101852943A (en) | Polarizer of liquid crystal screen | |
| KR20180074544A (en) | Cover Window and Flexible Display Comprising the Same | |
| CN110031920B (en) | Optical laminate | |
| US20200333833A1 (en) | Display device and method for manufacturing the same | |
| CN111161634B (en) | Optical film | |
| JPWO2018179893A1 (en) | Optical film and front plate of image display apparatus having the same, image display apparatus, mirror with image display function, resistive touch panel, and capacitive touch panel | |
| WO2023124563A1 (en) | Shell assembly and preparation method therefor, and electronic device | |
| CN113683807A (en) | Optical flexible cover plate structure | |
| CN112592506B (en) | Hard coating film, window comprising same, and image display device | |
| CN111499893B (en) | Optical film, flexible display device, and resin composition | |
| JP2017128083A (en) | Method for producing laminate, method for manufacturing display device, and laminate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 213000 No.20 Changyang Road, West Taihu science and Technology Industrial Park, Wujin District, Changzhou City, Jiangsu Province Applicant after: Xinlun electronic materials (Changzhou) Co.,Ltd. Address before: 213000 No.20 Changyang Road, West Taihu science and Technology Industrial Park, Wujin District, Changzhou City, Jiangsu Province Applicant before: Xinlun Technology (Changzhou) Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |