Preparation method of flexible hydrophobic dielectric film for electrowetting device

A dielectric film and electrowetting technology, applied in the field of material preparation, can solve the problems of small dielectric constant, poor substrate adhesion, unfavorable mold rotation process, etc., and achieve the effect of simple preparation method and easy material

Inactive Publication Date: 2019-09-24
SOUTH CHINA NORMAL UNIVERSITY
View PDF7 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the thickness of the traditional single-layer Teflon-based hydrophobic dielectric layer is generally tens to hundreds of nanometers, which is not conducive to the realization of the transfer molding process; therefore, in order to realize the transferable device processing technology, it is necessary to increase the hydrophobic dielectric The thickness of the layer facilitates the simplification of the process and the preparation of devices with reliable and stable performance
[0003] The commonly used hydrophobic dielectric layer material AF1600 has good hydrophobicity, but has a small dielectric constant and poor adhesion to the substrate; moreover, in electrowetting applications, the driving voltage increases with the increase of its thickness. Big

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of flexible hydrophobic dielectric film for electrowetting device
  • Preparation method of flexible hydrophobic dielectric film for electrowetting device
  • Preparation method of flexible hydrophobic dielectric film for electrowetting device

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0032] refer to figure 1 , the preparation method according to the present invention comprises the following steps:

[0033] 1) adding the fluoropolymer and the ionic liquid to the solvent to react to obtain a mixed solution, and directly coating the mixed solution on the surface of the substrate;

[0034] 2) curing by heating in a vacuum oven at 70 to 110°C for 4 to 40 hours to obtain an ion gel layer;

[0035] 3) Coating a hydrophobic layer on the surface of the ion gel layer to obtain a hydrophobic dielectric composite film, which can be used in electrowetting devices.

[0036] Preferably, as step 1), the fluorine-containing polymer is selected from poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) or poly(styrene-b-methyl methacrylate-b- Styrene) ([SMS]). Among them, vinylidene fluoride-co-hexafluoropropylene is a copolymer of vinylidene fluoride and hexafluoroisobutylene, and the copolymerization makes the crystallinity lower, so it has a larger amorphous reg...

Embodiment 1

[0056] 1. Synthesis of gel solution. Add 0.2 g of fluorine-containing polymer P(VDF-HFP) particles into a 50 mL flask, the weight-average molecular weight of the fluorine-containing polymer P(VDF-HFP) is 400,000, and the number-average molecular weight is 130,000. 0.7 g of ionic liquid [EMIM][TFSI] and 9.1 g of acetone were added. The reactants were magnetically stirred in an oil bath reactor at 60° C. for 3.5 hours to ensure that the fluoropolymer and the ionic liquid could be completely dissolved and reacted to obtain a mixed solution.

[0057] 2. The gel solution is spin-coated to form a film. Firstly, ultrasonically clean the ITO glass substrate, and dry it with nitrogen gas for later use. Then drop the mixed solution prepared in step 1) on it, adjust the rotation speed to 1500r / min, and spin coat to obtain an ion gel layer. The samples were put into a vacuum drying oven for heating and curing at a temperature of 70°C for 30 hours. Ensure that the solvent is completely...

Embodiment 2

[0061] 1. Synthesis of gel solution. Add 0.7 g of fluoropolymer P(VDF-HFP) particles into a 50 mL flask, the fluoropolymer has a weight molecular weight of 400,000 and a number average molecular weight of 130,000. 2.6 g of ionic liquid [EMIM][TFSI] and 6.7 g of acetone were added. The reactant was magnetically stirred in an oil bath reactor at 60° C. for 3.5 h to ensure that the copolymer and the ionic liquid could be completely dissolved and reacted to obtain a mixed solution.

[0062] 2. The gel solution is spin-coated to form a film. Firstly, ultrasonically clean the ITO glass substrate, and dry it with nitrogen gas for later use. Then drop the mixed solution prepared in step 1) on it, adjust the rotation speed to 1500r / min, and spin coat to obtain an ion gel layer. The samples were put into a vacuum drying oven for heating and curing at a temperature of 70°C for 30 hours. Ensure that the solvent is completely evaporated to obtain an ion gel layer. The thickness of the...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
contact angleaaaaaaaaaa
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of a flexible hydrophobic dielectric film for an electrowetting device. The preparation method comprises the following steps that 1) a fluorine-containing polymer and ionic liquid are added into a solvent for a reaction to obtain a mixed solution, and the mixed solution is directly applied on the surface of a substrate; 2) heating is carried out in a vacuum drying box of 70-110 DEG C for 4-40 hours for curing, and an ionic gel layer is obtained; 3) the surface of the ionic gel layer is coated with a hydrophobic layer, and the composite hydrophobic dielectric film capable of being used for the electrowetting device is obtained. The method has the advantages that the process is simple, the composite film can be prepared in a large area, wherein the hydrophobic layer is used for providing a larger initial contact angle, the thickness of the ionic gel layer can reach ten microns or above and twenty micros or below, the thickness of the dielectric film is accordingly increased, the driving voltage cannot increase with the increase of the thickness, and the device capable of transferring the film can be achieved. The preparation method is simple and suitable for large-area preparation.

Description

technical field [0001] The invention relates to the field of material preparation, in particular to a method for preparing a flexible hydrophobic dielectric film used in electrowetting devices. Background technique [0002] Electrowetting (Electrowetting, EW) refers to the phenomenon of changing the wettability of the droplet on the electrode surface by applying a voltage between the conductive droplet and the electrode, that is, changing the contact angle, and causing the droplet to deform and displace. Electrowetting-on-Dielectric (EWOD) based on the dielectric layer is based on the traditional electrowetting model, and a dielectric layer is added between the conductive layer and the droplet to overcome the direct contact between the conductive liquid and the conductive layer. The disadvantage of easy electrolysis. A basic EWOD device consists of a conductive liquid droplet, a conductive solid substrate, and a dielectric film between the droplet and the substrate. Usuall...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08J7/04C08L27/16
CPCC08J7/04C08J2327/16Y02P20/54
Inventor 水玲玲覃晓凤唐彪周国富金名亮
Owner SOUTH CHINA NORMAL UNIVERSITY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap