CN103325442B - A kind of compound transparent electricity conductive film and preparation method thereof - Google Patents
A kind of compound transparent electricity conductive film and preparation method thereof Download PDFInfo
- Publication number
- CN103325442B CN103325442B CN201310261713.9A CN201310261713A CN103325442B CN 103325442 B CN103325442 B CN 103325442B CN 201310261713 A CN201310261713 A CN 201310261713A CN 103325442 B CN103325442 B CN 103325442B
- Authority
- CN
- China
- Prior art keywords
- conductive film
- metallic conduction
- coating
- conduction grid
- transparent electricity
- 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
Abstract
The present invention relates to a kind of compound transparent electricity conductive film and preparation method thereof, described compound transparent electricity conductive film is followed successively by substrate, metal level and conductive coating from bottom to top; Wherein said metal level is patterned metallic conduction grid; Described conductive coating is material with carbon element coating.Wherein, the area sum beyond metallic conduction grid accounts for more than 80% of film entire area; Material with carbon element can be carbon nano-tube or Graphene.Described conductive coating be full surface area coat on film, avoid blank parts non-conductive, achieve full surface area continuous conduction, reduce the sheet resistance of compound transparent electricity conductive film, improve the stability of compound transparent electricity conductive film.
Description
Technical field
The present invention relates to transparent conductive film and preparation method thereof, particularly a kind of compound transparent electricity conductive film and preparation method thereof.
Background technology
Transparent conductive film is a kind of film having satisfactory electrical conductivity and have high transmission rate in visible wavelength section.Current transparent conductive film has been widely used in the fields such as photovoltaic device, contact panel, flat panel display and electromagnetic shielding, has and the wide market space.
ITO, due to its excellent light transmission and conductivity, dominates the market of transparent conductive film always.But ITO transparent conductive film exposes several shortcoming.First, the producing cost of ito thin film is relatively high, and this is mainly because the required vacuum deposition device cost of its preparation is higher, and complex manufacturing; Moreover indium is rare element, and indium ore resources is limited; Three, ITO resist can be relatively poor around folding endurance, and the large area causing ito thin film to be difficult to realize volume to volume is produced.Therefore, the patterned transparent conductive film based on nano metal material becomes the best solution under above-mentioned background.This kind of transparent conductive film realizes high conductivity by forming the metal conductive wire of patterning at substrate surface, non-patterned part then ensure that light through, thus achieve film light transmission, as shown in Figure 1, wherein 1 is white space, ensures light transmission; 2 is metal grid lines, ensures conductivity.
Owing to have employed metal material as conducting medium, and by the photoelectric properties of the adjustment film of the flexible design of pattern, and can realize large-scale industrial production, therefore be considered to a most rising class transparent conductive film.Japanese fuji film is in " the 19th FPD research and development and manufacturing technology exhibition and seminar (FINETECHJAPAN) " held in April, 2009, put on display the grid type transparent conductive film that the said firm adopts silver salt exposure method to prepare first, its sheet resistance can change within the scope of 0.2 ~ 3000 Ω/, and visible light transmittance rate can reach more than 80%.The research team that Chinese Lekai Film Group Co Zou Jing academician (existing University Of Tianjin) leads, has also prepared transparent conductive film by silver salt method, has been mainly used in electromagnetic shielding.The mode that the research team that Suzhou research in nanotechnology institute of Chinese Academy of Sciences Cui Zheng teaches then have employed nano impression has prepared grid type transparent conductive film, and the transparent conductive film sheet resistance obtained is 10 Ω/, and light transmittance is more than 85%.And the method adopting the mode of printing directly to prepare metal grate also have recently emerged report.The transparent conductive film that it is target that Dai Nippon Printing (DIC) adopts print process to develop with alternative ito film, is characterized in forming fine net-like pattern by conductive silver particle, and carries out continuous seepage in reel-to-reel mode.Japan prefecture is that (GUNZE) have developed the transparent conductive film adopting printing development to manufacture, and in " NanoTech2010 international nanotechnology is comprehensively opened up and technical conference " upper exhibition, the feature of this film adopts the screen printing technique improved to form pattern.Germany PolyIC also obtains the grid type transparent conductive film of photoelectric properties excellence by the mode of printing, graphics resolution is 15 μm, and light transmittance is greater than 80%.
Due to the characteristic of patterned transparent conductive film, cause it can not expire version continuous conduction, which has limited the application in some aspects of patterned transparent conductive film, as when as transparency electrode in photovoltaic device, greatly reduce the electricity conversion of device.
Therefore, provide one can expire version continuous conduction, transparent conductive film that the sheet resistance reducing compound transparent electricity conductive film also can stop metal grate to be oxidized and preparation method thereof just becomes the technical barrier that this technical field is badly in need of solving.
Summary of the invention
An object of the present invention is to provide one can expire version continuous conduction, the transparent conductive film that the sheet resistance reducing compound transparent electricity conductive film also can stop metal grate to be oxidized.
Above-mentioned purpose of the present invention is achieved through the following technical solutions:
A kind of compound transparent electricity conductive film, is followed successively by substrate, metal level and conductive coating from bottom to top; Wherein said metal level is patterned metallic conduction grid; Described conductive coating is material with carbon element coating.
A kind of optimal technical scheme, is characterized in that: the material with carbon element coating in described conductive coating is carbon nano-tube or Graphene.
A kind of optimal technical scheme, is characterized in that: described substrate is flexible and transparent.
A kind of optimal technical scheme, it is characterized in that: in described metal level, the area sum beyond described metallic conduction grid accounts for more than 80% of film entire area.
A kind of optimal technical scheme, is characterized in that: described metallic conduction grid is Nano Silver or Nanometer Copper.
A kind of optimal technical scheme, is characterized in that: the figure of described metallic conduction grid be square, rectangle, rhombus, circle, etc. the combination of one or more in hexagon, equilateral triangle.
A kind of optimal technical scheme, is characterized in that: the thickness of described metal level is between 200nm-5 μm.
A kind of optimal technical scheme, is characterized in that: the thickness of described conductive coating is less than 100nm.
Another object of the present invention is to provide a kind of preparation method of above-mentioned compound transparent electricity conductive film.
Above-mentioned purpose of the present invention reaches by the following technical programs:
A preparation method for compound transparent electricity conductive film, comprises the following steps:
(I), design according to demand and determine the three-dimensional structure of the metallic conduction grid of film;
(II) mask-making technology of laser corrosion or laser engraving, is used to make metallic conduction grid forme;
(III), sintered by intaglio printing mode type metal conductive grid;
(IV), by material with carbon element printing or be coated on metallic conduction grid transparent conductive film surface, make compound transparent electricity conductive film.
A kind of optimal technical scheme, is characterized in that: described in described step (I), the design procedure of the three-dimensional structure of metallic conduction grid comprises:
(1) the selected raw material making transparent conductive film, comprises the substrate of flexible and transparent, conductive metal material and material with carbon element;
(2) the light transmittance a of the flexible and transparent substrate of fixing thickness is measured;
(3) under the prerequisite meeting a × b × c>t, determine geometrical form and the live width d of metallic conduction grid, wherein t is the visible light transmittance rate of required compound transparent electricity conductive film, b is the ratio that glazed area beyond metallic conduction grid accounts for film entire area, and c is the light transmittance of the conductive coating of fixing thickness;
(4) according to the relation of conductive ink resistivity of water, solid content and the rate of transform of printing and the sheet resistance of required metallic conduction grid, the ink cell degree of depth of metallic conduction grid forme is determined.
A kind of optimal technical scheme, is characterized in that: described in described step (III), conductive ink is nano metal electrically conductive ink or nano-copper conductive ink.
A kind of optimal technical scheme, is characterized in that: described in described step (IV), material with carbon element is carbon nano-tube or Graphene.
A kind of optimal technical scheme, is characterized in that: the coating of material with carbon element described in described step (IV) is for being coated with or blade coating.
The invention has the advantages that:
Compound transparent electricity conductive film provided by the invention, by carbon nano-tube, graphene dispersing solution printing or the metal grate surface coating printing, fills the blank parts of metal grate, its blank parts is conducted electricity, reach the object of the full version continuous conduction of film; Meanwhile, reduce the sheet resistance of composite transparent conductive film, and stop the oxidation of metal grate.
Below by the drawings and specific embodiments, the present invention will be further described, but and do not mean that limiting the scope of the invention.
Accompanying drawing explanation
Fig. 1 is the principle schematic of grid type transparent conductive film;
Fig. 2 is the three-dimensional structure schematic diagram of metallic conduction grid forme;
Fig. 3 is the cross sectional representation of metallic conduction grid forme;
Fig. 4 is the stereochemical structure schematic top plan view of compound transparent electricity conductive film prepared by the embodiment of the present invention 1;
Fig. 5 is the cross sectional representation of compound transparent electricity conductive film prepared by the embodiment of the present invention 1.
Embodiment
Embodiment 1: make compound transparent electricity conductive film with intaglio printing metallic conduction grid and material with carbon element compound
In the present embodiment, use the mask-making technology of laser engraving to make metallic conduction grid forme, as shown in Figure 2, its sectional view as shown in Figure 3 for the three-dimensional structure schematic diagram of gained metallic conduction grid forme, wherein d is groove width (=grid live width), and h is the ink cell degree of depth.
Fig. 4 is the stereochemical structure schematic top plan view of compound transparent electricity conductive film prepared by the present embodiment, Fig. 5 is the cross sectional representation of compound transparent electricity conductive film prepared by the present embodiment, wherein, the substrate PET of 3 expression flexible and transparents, being the metallic conduction grid 4 printed by gravure mode on substrate 3, is the material with carbon element coating 5 on the full surface of one deck above metallic conduction grid 4.
As shown in Figure 2, be the three-dimensional structure schematic diagram of metallic conduction grid forme; As shown in Figure 3, be the cross sectional representation of metallic conduction grid forme; The intaglio plate grid of metallic conduction grid forme is quadrate array, and the foursquare length of side is 500 μm, and groove width d is 15 μm, ink cell degree of depth h value 10 μm.Flexible and transparent substrate 3 is PET, and thickness is 88 μm, light transmittance a=91%.
It is elemental silver that the metallic conduction grid 4 of intaglio printing sinters rear, and silver metal conductive grid is evenly distributed in transparent substrates, and is interconnected, and silver film thickness is about 2 μm, and silver-colored grid live width is 20 μm.Beyond the metallic conduction grid printed out, region area accounts for the ratio b=92.16% of film entire area.The light transmittance c=96% of the conductive coating of the material with carbon element (carbon nano-tube) of the fixing thickness of coating.The visible light transmittance rate of compound transparent electricity conductive film is 80.51%, and sheet resistance is 1.8 Ω/, and the full version continuous conduction of gross area.
The concrete steps preparing above-mentioned compound transparent electricity conductive film are as follows:
I, design the 3-D graphic of compound transparent electricity conductive film according to demand, thus determine the gravure plate-making parameter needed for type metal conductive grid.Design procedure specifically comprises: (1) selected light transmittance is the flexible and transparent substrate PET of more than 90%, visible light transmittance rate a=91%, thickness 88 μm; Material with carbon element coating 5 is carbon nanotube coating, and its thickness is 45nm, light transmittance c=96%; Conductive ink is the Nano silver conductive ink of particle diameter between 50-100nm, and solid content is 50% silver medal electrically conductive ink, viscosity 142mpas; (2) the design objective t > 80%(visible light transmittance rate of compound transparent electricity conductive film light transmittance) and a × b × c > t, obtain b > 92.16%; Select the square shape intaglio plate metallic conduction grid that resistance isotropism is good, under the prerequisite meeting b, in conjunction with printing lines amplification degree, determine intaglio plate metallic conduction grid live width d=15 μm; (3) solid content of silver-colored ink is 50%, sintering temperature 120 DEG C, time 5min, institute's measuring resistance rate 1 × 10
-4Ω cm.According to formula
wherein ρ is resistivity, R is sheet resistance, W is the thickness of metallic conduction grid, as the thickness W=2 μm of metallic conduction grid, the sheet resistance of metal grate is 5 Ω/, and the solid content of Nano silver conductive ink is 50%, and the rate of transform of Nano silver conductive ink is 40%, calculate the ink cell degree of depth h=10 μm of forme, meet design requirement.
II, use laser engraving platemaking machine, prepare metallic conduction grid groove on gravure cylinder surface; In order to increase the press resistance rate of forme, by gravure cylinder chrome-faced.
III, metal (Nano Silver ink) conductive grid using intaglio press volume to volume to design at the surface printing of PET, metal (Nano Silver ink) conductive grid of printing heats 5min on the heating plate of 120 DEG C, is sintered by silver-colored ink, forms conductive silver grid.
IV, use 4# Meyer rod (instrument for being coated with) by solid content be 0.1% carbon nano tube dispersion liquid (its dispersant is water, carbon nano-tube is ultra-pure Single Walled Carbon Nanotube, model is NTST, Chengdu Organical Chemical Co., Ltd., Chinese Academy of Sciences produces) coat on Nano Silver metallic conduction grid nesa coating, dispersion liquid is dry at 25 DEG C, forms carbon nanotube conducting coating.
The detailed description of above embodiment, is intended to the substantive distinguishing features being convenient to understand technical solution of the present invention, not limits the scope of the present invention size with this.In above embodiment, by changing the thickness of duty ratio on forme (grate area and grid beyond blank parts area ratio) and material with carbon element conducting film, can freely control the light transmittance of nesa coating; Also by changing the solid content of the forme ink cell degree of depth (value 5-30 μm), Nano Silver ink and material with carbon element dispersion liquid, the sheet resistance of nesa coating is freely controlled; Described electrically conductive ink also comprises the nano-copper ink etc. that market can be purchased; Described material with carbon element also can be the dispersion liquid of the Graphene that market can be purchased; Described mode of printing can also be conventional flexo, ink-jet, offset printing etc.Described coating can be conventional being coated with or blade coating.The unit cell shapes of described metallic conduction grid also comprise rectangle, rhombus, circle, etc. one or more compounds in hexagon, equilateral triangle.
Compound transparent electricity conductive film of the present invention, comprises flexible and transparent substrate, metal level and conductive coating from bottom to top; Wherein metal level is patterned metal grate, and area beyond described metal grate and account for all surfaces long-pending more than 80%; Described conductive coating be full surface area coat on film, avoid blank parts non-conductive, achieve full surface area continuous conduction, reduce the sheet resistance of compound transparent electricity conductive film, improve the stability of compound transparent electricity conductive film.
Claims (4)
1. a compound transparent electricity conductive film, is followed successively by substrate, metal level and conductive coating from bottom to top; Wherein said metal level is patterned metallic conduction grid; Described conductive coating is material with carbon element coating;
Its preparation process is as follows:
(I), design according to demand and determine the three-dimensional structure of the metallic conduction grid of film;
(II) mask-making technology of laser corrosion or laser engraving, is used to make metallic conduction grid forme;
(III), sintered by gravure printing mode conductive ink type metal conductive grid;
(IV), by material with carbon element printing or be coated on metallic conduction grid transparent conductive film surface, make compound transparent electricity conductive film;
Described in described step (I), the specific design step of the three-dimensional structure of metallic conduction grid is as follows:
(1) selected light transmittance is the flexible and transparent substrate PET of more than 90%, visible light transmittance rate a=91%, thickness 88 μm; Material with carbon element coating is carbon nanotube coating, and its thickness is 45nm, light transmittance c=96%; Conductive ink is the Nano silver conductive ink of particle diameter between 50-100nm, and solid content is 50% silver medal electrically conductive ink, viscosity 142mpas; (2) the design objective t > 80% of compound transparent electricity conductive film light transmittance and a × b × c > t, obtains b > 92.16%; Select the square shape intaglio plate metallic conduction grid that resistance isotropism is good, under the prerequisite meeting b, in conjunction with printing lines amplification degree, determine intaglio plate metallic conduction grid live width d=15 μm; (3) solid content of silver-colored ink is 50%, sintering temperature 120 DEG C, time 5min, institute's measuring resistance rate 1 × 10
-4Ω cm; According to formula
wherein ρ is resistivity, R is sheet resistance, W is the thickness of metallic conduction grid, as the thickness W=2 μm of metallic conduction grid, the sheet resistance of metal grate is 5 Ω/, and the solid content of Nano silver conductive ink is 50%, and the rate of transform of Nano silver conductive ink is 40%, calculate the ink cell degree of depth h=10 μm of forme, meet design requirement.
2. compound transparent electricity conductive film according to claim 1, is characterized in that: described in described step (III), conductive ink is nano metal electrically conductive ink.
3. compound transparent electricity conductive film according to claim 1, is characterized in that: described in described step (IV), material with carbon element is carbon nano-tube or Graphene.
4. compound transparent electricity conductive film according to claim 1, is characterized in that: the coating of material with carbon element described in described step (IV) is for being coated with or blade coating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310261713.9A CN103325442B (en) | 2013-06-27 | 2013-06-27 | A kind of compound transparent electricity conductive film and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310261713.9A CN103325442B (en) | 2013-06-27 | 2013-06-27 | A kind of compound transparent electricity conductive film and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103325442A CN103325442A (en) | 2013-09-25 |
| CN103325442B true CN103325442B (en) | 2015-11-11 |
Family
ID=49194132
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310261713.9A Active CN103325442B (en) | 2013-06-27 | 2013-06-27 | A kind of compound transparent electricity conductive film and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103325442B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3880746A4 (en) * | 2018-11-13 | 2022-09-14 | Chasm Advanced Materials, Inc. | Transparent conductive circuit |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103545021B (en) * | 2013-11-06 | 2016-06-29 | 北京印刷学院 | A kind of metal grid type transparent conductive film and preparation method thereof |
| CN105023629B (en) * | 2014-04-28 | 2017-02-01 | 中国科学院上海硅酸盐研究所 | Graphene-copper nano wire composite film and preparation method |
| CN103992041A (en) * | 2014-04-30 | 2014-08-20 | 天津宝兴威科技有限公司 | Manufacturing method of nano metal grid transparent electro-conductive glass |
| CN105280840B (en) * | 2014-07-09 | 2018-05-08 | Tcl集团股份有限公司 | A kind of flexible transparent electrode and preparation method thereof |
| KR101764278B1 (en) * | 2015-06-10 | 2017-08-04 | 오현석 | Electromagnetic shielding material by using Nano Structure |
| CN105589599A (en) * | 2015-12-24 | 2016-05-18 | 无锡格菲电子薄膜科技有限公司 | Method for manufacturing graphene touch sensor |
| CN105751621A (en) * | 2016-04-29 | 2016-07-13 | 苏州巨邦新材料科技有限公司 | Efficient conductive composite material and preparation process |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6115171A (en) * | 1997-01-23 | 2000-09-05 | Nippon Mitsubishi Oil Corporation | Electrochromic device |
| CN101950771A (en) * | 2010-07-27 | 2011-01-19 | 中国科学院苏州纳米技术与纳米仿生研究所 | Method for preparing compound electrode |
| CN102569432A (en) * | 2010-12-17 | 2012-07-11 | 国家纳米科学中心 | Transparent electrode material and preparation method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1269342A (en) * | 1984-04-30 | 1990-05-22 | Ppg Industries Ohio, Inc. | Method of electroforming articles using a photomask mandrel |
-
2013
- 2013-06-27 CN CN201310261713.9A patent/CN103325442B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6115171A (en) * | 1997-01-23 | 2000-09-05 | Nippon Mitsubishi Oil Corporation | Electrochromic device |
| CN101950771A (en) * | 2010-07-27 | 2011-01-19 | 中国科学院苏州纳米技术与纳米仿生研究所 | Method for preparing compound electrode |
| CN102569432A (en) * | 2010-12-17 | 2012-07-11 | 国家纳米科学中心 | Transparent electrode material and preparation method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3880746A4 (en) * | 2018-11-13 | 2022-09-14 | Chasm Advanced Materials, Inc. | Transparent conductive circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103325442A (en) | 2013-09-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103325442B (en) | A kind of compound transparent electricity conductive film and preparation method thereof | |
| CN104835555B (en) | A kind of preparation method of pattern metal transparent conductive film | |
| CN102222538B (en) | Graphical flexible transparent conductive film and preparation method thereof | |
| Xue et al. | Nanowire-based transparent conductors for flexible electronics and optoelectronics | |
| CN102063951B (en) | Transparent conductive film and manufacturing method thereof | |
| Yu et al. | Transparent conductive film with printable embedded patterns for organic solar cells | |
| Mohl et al. | Self-assembled large scale metal alloy grid patterns as flexible transparent conductive layers | |
| EP3660903B1 (en) | Transparent light emitting element display | |
| Anh Dinh et al. | Silver nanowires: a promising transparent conducting electrode material for optoelectronic and electronic applications | |
| KR102075272B1 (en) | Transparent light emitting device display | |
| CN106611627A (en) | High-quality carbon nanotube transparent conductive film, preparation method thereof and applications | |
| CN105304157A (en) | Transparent conductive thin film with conductive copper network and preparation method thereof | |
| Lin et al. | High-resolution and large-size stretchable electrodes based on patterned silver nanowires composites | |
| Kim et al. | Simple, fast, and scalable reverse-offset printing of micropatterned copper nanowire electrodes with sub-10 μm resolution | |
| Cui et al. | 27.5 L: Late‐News Paper: Hybrid Printing of High Resolution Metal Mesh as A Transparent Conductor for Touch Panels and OLED Displays | |
| Hokari et al. | Development of simple high-resolution embedded printing for transparent metal grid conductors | |
| CN107610814A (en) | A kind of transparency electrode based on super thin metal grid and preparation method thereof | |
| Zhang et al. | Microscale Hybrid Additive Manufacturing of Ultra‐Fine, Embedded Cu/Ag (shell)–P4VP (core) Grid for Flexible Transparent Electrodes | |
| Qi et al. | Microscale hybrid 3D printed ultrahigh aspect ratio embedded silver mesh for flexible transparent electrodes | |
| CN103996454A (en) | Manufacturing method for nanometal grid transparent conductive substrate | |
| Zhong et al. | Fabrication of Highly Flat, Flexible Mesh Electrode for Use in Photovoltaics | |
| CN103412662A (en) | Touch panel and preparation method thereof | |
| Huang et al. | Selective laser ablation preparation of Ag grid transparent electrodes with fractal-combined structures and optimization of fractal grid pitch | |
| Shin et al. | Moiré-fringeless transparent conductive films with a random serpentine network of medium-field electrospun, chemically annealed silver microfibres | |
| Arango et al. | Direct writing and electro-mechanical characterization of Ag micro-patterns on polymer substrates for flexible electronics |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20221025 Address after: 361027 Unit 01-2, 10th Floor, Building B13, Xiamen Biomedical Industrial Park, No. 2074, Wengjiao West Road, Haicang District, Xiamen, Fujian Patentee after: Xiamen Zhongke Intelligent Medical Technology Co.,Ltd. Address before: 102600 No. 1, Section 2, Xinghua Street, Daxing District, Beijing Patentee before: BEIJING INSTITUTE OF GRAPHIC COMMUNICATION |