Electrochromic display panel and electronic paper
Technical Field
The invention relates to an electrochromic display panel and electronic paper, and belongs to the technical field of display.
Background
Electrochromism (EC) refers to a phenomenon in which optical properties (reflectivity, transmittance, absorption, etc.) of a material undergo a stable and reversible color change under the action of an external electric field, and is visually represented as a reversible change in color and transparency. Materials having electrochromic properties are referred to as electrochromic materials, and devices made with electrochromic materials are referred to as electrochromic devices. Electrochromic materials are one of the hot spots of material science research in recent years. The electrochromic material is an important component in an electrochromic device and dominates the electrochromic performance of the device. Electrochromic materials can be classified into anodic electrochromic materials (ion-intercalation coloring) and cathodic electrochromic materials (ion-extraction coloring) according to the structural properties of the materials. The anode electrochromic material and the cathode electrochromic material can be assembled into a complementary electrochromic device, and the complementary device can improve the whole electrochromic performance such as optical contrast, color change, spectral absorption range and the like. At present, the existing electrochromic display panel and electronic paper have the following problems: the non-uniformity of the applied electric field is large, thereby affecting the dielectric strength of the dielectric; under the same other conditions, the more uneven the electric field is, the lower the dielectric strength of the dielectric is, and the other materials are likely to contact the dielectric layer to cause corrosion reaction.
Disclosure of Invention
The invention aims to provide an electrochromic display panel and electronic paper, which have the advantages of uniform electric field distribution among electrodes, better display effect, simple structure and easy preparation.
In order to achieve the purpose, the invention provides the following technical scheme: an electrochromic display panel comprises a first substrate, an electrochromic pixel array and a second substrate which are sequentially arranged, wherein the electrochromic pixel array comprises a plurality of electrochromic units which are arranged in an array and independently controlled, and each electrochromic unit comprises a first electrode, an electrochromic pixel layer and a second electrode which are sequentially arranged; the first electrode is provided with a first opposite surface opposite to the second electrode, the second electrode is provided with a second opposite surface opposite to the first electrode, and a plurality of micro-nano structures are arranged on the first opposite surface and/or the second opposite surface.
Further, the micro-nano structure is a concave-convex groove type structure.
Further, the widths of the groove shapes of the concave-convex groove type structure are the same or different; the depths of the groove types are the same or different; the shape of the groove is rectangular, trapezoidal or arc.
Further, the micro-nano structures are distributed periodically or non-periodically.
Further, the electrochromic display panel further comprises a white reflective layer disposed between the first substrate and the electrochromic pixel array.
Further, the electrochromic display panel further comprises an adhesive layer, wherein the adhesive layer is arranged between the white reflecting layer and the electrochromic pixel array, and the electrochromic pixel array is adhered to the white reflecting layer through the adhesive layer.
Further, the white reflective layer is formed of an adhesive polymer resin and white particles, and the electrochromic pixel array is adhered on the white reflective layer.
Further, the first electrode and/or the second electrode are transparent electrodes.
Furthermore, the electrochromic unit also comprises an ion storage layer and a conductive layer which are sequentially stacked and arranged between the first electrode and the electrochromic pixel layer.
Further, the ion storage layer and the conductive layer are solid structures.
Further, the first electrode is embedded with the ion storage layer.
Further, an electrochromic material is arranged in the electrochromic pixel layer, and the electrochromic material is selected from any one or more of an organic electrochromic material, an inorganic electrochromic material or a composite electrochromic material.
Further, the inorganic electrochromic material comprises metal oxide, preferably tungsten trioxide and nickel oxide.
Further, the organic electrochromic material is preferably any one or more of viologens, isophthalates, metal phthalocyanines, pyridine metal complexes, polyanilines, polypyrroles and polythiophenes.
The invention also provides electronic paper which comprises the electrochromic display panel.
Compared with the prior art, the invention has the beneficial effects that: according to the electrochromic display panel and the electronic paper, the micro-nano structure is arranged on the first electrode and/or the second electrode in the electrochromic pixel array, so that the contact area of the electrochromic display panel and the electronic paper can be increased, the electrochromic display panel has better electrochemical performance, the electric field between the two electrodes is more uniformly distributed, the conductive effect and the response speed of the electrochromic display panel are enhanced, the structure is simple, and the preparation is easy.
In addition, the electrochromic display panel and the electronic paper fix the electrochromic pixel array on the white reflecting layer in a bonding mode, so that the packaging step of a liquid electrochromic material is omitted, the phenomena that an electrode above a gap collapses and is easy to leak due to pressure difference are avoided, the production cost is saved, and the product quality is improved.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.
Drawings
FIG. 1 is a top view of an electrochromic display panel according to the invention;
fig. 2a and 2b are schematic structural diagrams of an electrochromic display panel according to the present invention;
fig. 3 and 4 are schematic structural diagrams of micro-nano structures in an electrochromic display panel according to the invention;
FIG. 5 is a schematic view of another embodiment of an electrochromic display panel according to the invention;
fig. 6 is a schematic structural diagram of an electrochromic display panel according to a first embodiment of the invention;
fig. 7 is a schematic structural diagram of an electrochromic display panel according to a second embodiment of the invention;
fig. 8 is a schematic structural diagram of an electrochromic display panel according to a third embodiment of the present invention.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
It should be noted that: the terms "upper", "lower", "left", "right", "inner" and "outer" of the present invention are used for describing the present invention with reference to the drawings, and are not intended to be limiting terms.
Referring to fig. 1 and 2a, in a vertical direction 10, the electrochromic display panel of the present invention includes a first substrate 1, an electrochromic pixel array layer 3, and a second substrate 4, which are sequentially disposed, where the electrochromic pixel array layer 3 includes a plurality of electrochromic units 30 arranged in an array and independently controlled, and each electrochromic unit 30 includes a first electrode 31, an electrochromic pixel layer 32, and a second electrode 33, which are sequentially disposed, where the first electrode 31 has a first opposite surface 311 opposite to the second electrode 33, the second electrode 33 has a second opposite surface 331 opposite to the first electrode 31, and the first opposite surface 311 and/or the second opposite surface 331 are provided with a plurality of micro-nano structures 5.
Referring to fig. 2b, the electrochromic display panel of the invention further includes a reflective layer 2, and the reflective layer 2 is disposed between the first substrate 1 and the electrochromic pixel array layer 3. In the vertical direction 10, the electrochromic display panel comprises a first substrate 1, a reflecting layer 2, an electrochromic pixel array layer 3 and a second substrate 4 which are sequentially stacked from bottom to top, the electrochromic pixel array layer 3 comprises a plurality of array arrangements and independently controlled electrochromic units 30, each electrochromic unit 30 comprises a first electrode 31, an electrochromic pixel layer 32 and a second electrode 33 which are sequentially arranged, wherein the first electrode 31 is provided with a first opposite surface 311 opposite to the second electrode 33, the second electrode 33 is provided with a second opposite surface 331 opposite to the first electrode 31, and a plurality of micro-nano structures 5 are arranged on the first opposite surface 311 and/or the second opposite surface 331.
Here, the micro-nano structure 5 is provided on the second opposing surface 331 as an example, but the structure is not limited to this. And, the micro-nano structure 5 can be formed by a photolithography process, a laser etching process, a nano-imprinting process, and the like. The first electrode 31 and the second electrode 33 are generally rectangular or circular in shape, and the first electrode 31 and the second electrode 33 will be described as being rectangular in shape. In consideration of technical difficulty and cost, the micro-nano structure 5 is preferably an uneven groove type structure, and the uneven groove type structure 5 may be periodically or non-periodically distributed on the second electrode 33. Moreover, the groove shapes of the concave-convex groove-shaped structure 5 have the same or different widths; the depths of the groove shapes are the same or different; the groove shape is rectangular, trapezoidal or arc
Referring to fig. 3, when the groove-and-projection type structures 5 are periodically distributed on the second opposite surface 331 of the second electrode 33, the electric field between the first electrode 31 and the second electrode 33 is uniformly distributed. Alternatively, referring to fig. 4, since the electric field at the edge of the second electrode 33 is more easily distributed unevenly, the sub-concavo-convex groove-shaped structures 5 are distributed non-periodically on the second opposite surface 331 of the second electrode 33, and the distribution of the concavo-convex groove-shaped structures 5 near the edge of the second electrode 33 is tighter than the distribution near the center of the second electrode 33. Of course, the groove-and-projection type structure 5 may also be provided on the first electrode 31 alone, or on both the first electrode 31 and the second electrode 33. The first electrode 31 and the second electrode 33 may have a circular structure, and they are arranged in the same manner as described above, and will not be described again.
In the present invention, the electrochromic cell 30 is further provided with a solid ion storage layer 34 and a conductive layer 35, and the ion storage layer 34 and the conductive layer 35 are sequentially laminated between the first electrode 31 and the electrochromic pixel layer 32. An ion storage layer 34 is disposed on the first electrode 31, a conductive layer 35 is disposed on the ion storage layer 34, and an electrochromic pixel layer 32 is disposed on the conductive layer 35.
In the present invention, the white reflective layer 2 is formed of a polymer resin which may be selected from any one including a phenol resin, an epoxy resin, a polyamide resin, a urethane resin or an acrylic resin, and white particles which may be selected from any one or more of aluminum oxide, zinc oxide, titanium oxide or silicon dioxide. Referring to fig. 5, when the white reflective layer 2 has no adhesiveness, the electrochromic pixel array 3 may be adhered to the white reflective layer 2 by disposing an adhesive layer 21 between the white reflective layer 2 and the electrochromic pixel array 2, wherein the thickness of the white reflective layer 2 is preferably 1-40 μm, and the thickness of the adhesive layer 21 is preferably 1-40 μm. When the white reflective layer 2 is adhesive, i.e. a viscous polymer resin is selected, the electrochromic pixel array 3 may be directly adhered to the white reflective layer 2, wherein the thickness of the white reflective layer 2 is preferably 10-70 μm. Through the arrangement, the packaging step of the liquid electrochromic material is omitted, the phenomena that the electrode above the gap collapses and liquid leakage easily occurs due to pressure difference are avoided, the stability and the flatness of the electrochromic display panel with the structure are ensured, and the phenomena that Newton rings and the like are not beneficial to the display effect can be avoided or reduced.
The electrochromic pixel layer 32 in the invention is provided with an electrochromic material, which is selected from any one of organic electrochromic materials, inorganic electrochromic materials or composite electrochromic materials, wherein the inorganic electrochromic materials comprise metal oxides, preferably tungsten trioxide and nickel oxide; the organic electrochromic material is preferably any one or more of viologens, isophthalates, metal phthalocyanines, pyridine metal complexes, polyanilines, polypyrroles and polythiophenes, and can be prepared by methods such as sputtering, chemical vapor deposition, sol-gel or evaporation, or can be prepared by drying and curing a liquid electrochromic material. The first electrode 31 and the second electrode 33 of the present invention are transparent electrodes selected from any one of Indium Tin Oxide (ITO), fluorine-doped tin oxide (FTO), or a conductive polymer. The first substrate 1 and the second substrate 4 may be transparent inorganic substrates, such as quartz or glass, or may be transparent plastics, or may be other commonly used transparent materials.
The invention also provides an electronic paper (not shown) comprising the electrochromic display panel, and other structures are all in the prior art and will not be described herein.
The present invention will be described in further detail with reference to specific examples.
Example one
Referring to fig. 6, the electrochromic display panel shown in this embodiment includes a first substrate 1-1, an electrochromic pixel array 1-2, and a second substrate 1-3, which are sequentially disposed from bottom to top, the electrochromic pixel array layer 1-2 includes a plurality of electrochromic units 1-20 arranged in an array and independently controlled, and the electrochromic units 1-20 include a first transparent electrode 1-21, an ion storage layer 1-22, a conductive layer 1-23, an electrochromic pixel layer 1-24, and a second transparent electrode 1-25, which are sequentially disposed from bottom to top. Wherein the first transparent electrode 1-21 has a first opposite surface 1-211 opposite to the second transparent electrode 1-25, and the second transparent electrode 1-25 has a second opposite surface 1-251 opposite to the first transparent electrode 1-21, in order to make the electric field distribution between the first transparent electrode 1-21 and the second transparent electrode 1-25 more uniform, in this embodiment, a plurality of concave-convex groove type structures 1-4 are arranged on the first opposite surface 1-211 and the second opposite surface 1-251, and the concave-convex groove type structures 1-4 are distributed more tightly near the edges of the transparent electrodes. By the arrangement, the electric field boundary effect can be avoided, and the electric field distribution is more uniform. In addition, the groove shapes of the concave-convex groove type structures 1-4 have the same width and depth; the shape of the groove is rectangular.
In this embodiment, the first transparent electrodes 1-21 and the second transparent electrodes 1-25 are both rectangular in configuration, but may be circular in other embodiments. The groove-and-projection type structures 1-4 of this embodiment are arranged on the first transparent electrodes 1-21 and the second transparent electrodes 1-25, and indeed, in other embodiments, the groove-and-projection type structures 1-4 may also be arranged on the first transparent electrodes 1-21 or the second transparent electrodes 1-25 individually.
Example two
Referring to fig. 7, the electrochromic display panel of the embodiment includes a first substrate 2-1, an electrochromic pixel array 2-2, and a second substrate 2-3, which are sequentially disposed from bottom to top, the electrochromic pixel array layer 2-2 includes a plurality of electrochromic units 2-20 arranged in an array and independently controlled, and the electrochromic units 2-20 include a first transparent electrode 2-21, an ion storage layer 2-22, a conductive layer 2-23, an electrochromic pixel layer 2-24, and a second transparent electrode 2-25, which are sequentially disposed from bottom to top. The first transparent electrode 2-21 has a first opposite surface 2-211 opposite to the second transparent electrode 2-25, and the second transparent electrode 2-25 has a second opposite surface 2-251 opposite to the first transparent electrode 2-21, in order to make the electric field distribution between the first transparent electrode 2-21 and the second transparent electrode 2-25 more uniform, in this embodiment, a plurality of periodically distributed concave-convex groove type structures 2-4 are arranged on the first opposite surface 2-211 and the second opposite surface 2-251, and the concave-convex groove type structures 2-4 are uniformly distributed on the second transparent electrode 2-25. In addition, the groove shapes of the concave-convex groove type structures 2-4 have the same width and depth; the shape of the groove is rectangular.
In this embodiment, the first transparent electrode 2-21 and the second transparent electrode 2-25 are both rectangular in configuration, but may be circular in other embodiments. The groove-and-projection type structure 2-4 of this embodiment is arranged on the first transparent electrode 2-21 and the second transparent electrode 2-25, and indeed, in other embodiments, the groove-and-projection type structure 2-4 may also be arranged on the first transparent electrode 2-21 or the second transparent electrode 2-25 separately.
EXAMPLE III
Referring to fig. 8, the structure of the electrochromic display panel of the present embodiment is basically the same as that of the first embodiment, and the difference is: the present embodiment is provided with a white reflective layer 3-5 and an adhesive layer 3-51 between the first substrate 3-1 and the electrochromic pixel array 3-2, and in the present embodiment, the white reflective layer 3-5 is composed of a phenol resin and dispersed titanium oxide and is provided on the first substrate 3-1 by a spin coating method. The thickness of the white reflective layer 3-5 was 20 μm, and the thickness of the adhesive layer 3-51 was 15 μm. By providing the adhesive layer 3-51, a better adhesion effect can be achieved than when the electrochromic pixel array 3-2 is adhered with an adhesive white reflective layer, so that the electrochromic pixel array 3-2 is more stably fixed on the white reflective layer 3-5.
In summary, the following steps: according to the electrochromic display panel and the electronic paper, the micro-nano structure is arranged on the first transparent electrode and/or the second transparent electrode in the electrochromic pixel array, so that the contact area of the micro-nano structure can be increased, the micro-nano structure has better electrochemical performance, the electric field between the two electrodes is distributed more uniformly, the conductive effect and the response speed of the micro-nano structure are enhanced, and the structure is simple and is easy to prepare. In addition, the electrochromic display panel and the electronic paper fix the electrochromic pixel array on the white reflecting layer in a bonding mode, so that the packaging step of a liquid electrochromic material is omitted, the phenomena that an electrode above a gap collapses and is easy to leak due to pressure difference are avoided, the production cost is saved, and the product quality is improved.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.