Method for rapidly stripping waste liquid crystal display polarizer

A liquid crystal display and polarizer technology, applied in chemical instruments and methods, solid waste removal, transportation and packaging, etc., can solve the problems of loss of use value, large amount of acetone, complicated steps, etc., to avoid toxic side effects and equipment requirements Low, the effect of increasing the peeling rate

Active Publication Date: 2018-09-14
SOUTH CHINA UNIV OF TECH
View PDF10 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, there are few domestic and foreign researches on the separation technology of polarizers and ITO glass substrates in waste liquid crystal displays, usually based on single resource recycling, and it is difficult to retain the original characteristics of the two during the separation process
Chinese patent CN 104793369A discloses a device for separating polarizers and glass substrates. The separation is mainly based on the physical properties of the materials. However, since it is difficult for pressure-sensitive adhesives to reduce the viscosity under this condition, the separation rate will be too low. Mechanical breakage can cause loss of indium resources on glass substrates
Chinese patent CN 103331295 A discloses a method and device for industrialized recycling of glass panels of waste liquid crystal displays, which is mainly recovered through the steps of physical exploitation, immersion in organic solvents and centrifugal separation. The processing cycle is too long, and it is difficult to apply to broken liquid crystals. Screen
Chinese patent CN 101690936 discloses a recycling method for waste thin-film transistor liquid crystal displays. In this method, the temperature of the glass substrate is directly raised to 190-250°C, and the polarizer is embrittled and then buried. The problem of resource utilization is not considered, and high-temperature treatment Although the pressure-sensitive adhesive can lose its viscosity, it is convenient to peel off the polarizer, but at the same time, because the polarizer is damaged, it loses its use value
However, acetone has strong volatility, so the above-mentioned existing research has a large amount of acetone and low stripping efficiency under the condition of long-time immersion.
In addition, the above studies all need to be soaked in acetone for the first time to remove the polarizer, and then soaked in acetone again to collect the liquid crystal. The steps are complicated, and for the waste liquid crystal screen with leakage, the steps of soaking in acetone again are redundant

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
  • Method for rapidly stripping waste liquid crystal display polarizer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] This embodiment provides a method for quickly peeling off the waste liquid crystal display polarizer:

[0032] 1. Use a flat screwdriver to pry open the metal frame of the waste liquid crystal display along the seam, take out the backlight module for recycling, and the well-preserved film can be reused, and the LCD screen, plastic frame, and metal frame are recycled separately.

[0033] 2. Use a knife to cut along the corner of the LCD screen to separate the upper and lower glass panels.

[0034] 3. Immerse the glass panel in 80°C water for 20 minutes. When the color of the polarizer is found to change from dark to light, take it out, and peel off the polarizer film layer composed of PET film, triacetate cellulose film and polyvinyl alcohol film in the polarizer. The peeled part will return to its original shape after the surface is naturally air-dried.

[0035] 4. Immerse the upper glass substrate with only the triacetate cellulose film in acetone for 15 minutes and t...

Embodiment 2

[0039] This embodiment provides a method for quickly peeling off the waste liquid crystal display polarizer:

[0040] 1. Use a flat screwdriver to pry open the metal frame of the waste liquid crystal display along the seam, take out the backlight module for recycling, and the well-preserved film can be reused, and the LCD screen, plastic frame, and metal frame are recycled separately.

[0041] 2. Use a knife to cut along the corner of the LCD screen to separate the upper and lower glass panels.

[0042] 3. Immerse the glass panel in 100°C water for 5 minutes. When the color of the polarizer is found to change from dark to light, take it out, and peel off the combined film layer of PET film, triacetate cellulose film and polyvinyl alcohol film in the polarizer. The peeled part will return to its original shape after the surface is naturally air-dried.

[0043] 4. Immerse the upper glass substrate with only the triacetate cellulose film in acetone for 15 minutes and the lower g...

Embodiment 3

[0046] This embodiment provides a method for quickly peeling off the waste liquid crystal display polarizer:

[0047]1. Use a flat screwdriver to pry open the metal frame of the waste liquid crystal display along the seam, take out the backlight module for recycling, and the well-preserved film can be reused, and the LCD screen, plastic frame, and metal frame are recycled separately.

[0048] 2. Use a knife to cut along the corner of the LCD screen to separate the upper and lower glass panels.

[0049] 3. Immerse the glass panel in 90°C water for 10 minutes. When the color of the polarizer is found to change from dark to light, take it out, and peel off the combined film layer of PET film, triacetate cellulose film and polyvinyl alcohol film in the polarizer. The peeled part will return to its original shape after the surface is naturally air-dried.

[0050] 4. Immerse the upper and lower glass substrates with only the triacetate cellulose film in acetone for 30 minutes to ma...

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

No PUM Login to view more

Abstract

The invention belongs to the technical field of waste liquid crystal display resource recovery, and particularly relates to a method for rapidly stripping a waste liquid crystal display polarizer. Themethod includes the steps: firstly, soaking a glass panel in a liquid crystal display screen in hot water, taking out the glass panel and then primarily stripping the glass panel to obtain a glass panel only adhered with a triacetate fiber film; secondly, soaking the glass panel in acetone to sharply reduce pressure-sensitive adhesiveness, and accordingly stripping the remaining triacetate fiberfilm. All parts of complete waste liquid crystal displays or waste liquid crystal displays with different breakage degrees can be completely separated, treatment time is as short as 1 hour, acetone soaking time is shorter than 30 minutes, dosage of the acetone can be reduced, the method is green and environmentally friendly, the film and a glass substrate can be separated by means of mechanical stirring or centrifugation after acetone soaking, and toxic and side effects of the acetone on human bodies are avoided. Stripping of the polarizer and liquid crystal recovery can be realized by one-time acetone soaking, and the stripped polarizer cannot be damaged by high temperature and can serve as a plastic recycled by pyrolysis or hydrolysis and the like.

Description

technical field [0001] The invention belongs to the technical field of resource recovery of waste liquid crystal displays, and in particular relates to a method for quickly peeling off polarizers of waste liquid crystal displays. Background technique [0002] Liquid crystal displays are formed by wrapping liquid crystals with two ITO glass substrates with polarizers attached. They are widely used in image display of mobile phones, notebooks, tablets and TVs. The amount of scrap is far greater than the amount of scrapped electronic products, so the research and development of its recycling technology is particularly critical. The material structures of polarizers, ITO glass substrates and liquid crystals are quite different. In order to maximize the recycling benefits, it is necessary to separate them. During the disassembly process, the liquid crystal is easily separated and dissolved, but the polarizer and the ITO glass substrate are firmly bonded. If they cannot be effect...

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): B09B3/00B09B5/00
CPCB09B5/00B09B3/40
Inventor 朱能武崔佳莹罗德亮吴平霄
Owner SOUTH CHINA UNIV OF TECH
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