Color conversion film and back light unit and display apparatus comprising the same

Patent metadata

Field	Value
Publication number	US-2016223728-A1
Application number	US-201615009447-A
Country	US
Kind code	A1
Filing date	Jan 28, 2016
Priority date	Jan 31, 2015
Publication date	Aug 4, 2016
Grant date	—

Abstract

The invention described in the present specification relates to a color conversion film including a resin matrix; and an organic fluorescent substance, wherein the color conversion film has a light emission peak with FWHM of 70 nm or less when irradiating light having a light emission peak of a 450 nm wavelength, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and a ratio of light emission intensity at 600 nm to light emission intensity at a maximum light emission wavelength is 1:3 or higher, a method for preparing the same, and a back light unit including the color conversion film.

First claim

1 . A color conversion film comprising:
a resin matrix; and an organic fluorescent substance, wherein the color conversion film has a light emission peak with FWHM of 70 nm or less when irradiating light having a light emission peak of a 450 nm wavelength, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and a ratio of light emission intensity at 600 nm to light emission intensity at a maximum light emission wavelength is 1:3 or higher.

2 . The color conversion film of claim 1 , wherein the organic fluorescent substance includes a first fluorescent substance and a second fluorescent substance, the first fluorescent substance has a maximum light emission wavelength in a 620 nm to 680 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and the second fluorescent substance has a maximum light emission wavelength in a 590 nm to 630 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

3 . The color conversion film of claim 1 , wherein the organic fluorescent substance includes a first fluorescent substance and a second fluorescent substance, the color conversion film has a maximum light emission wavelength in a 590 nm to 680 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and the first fluorescent substance has a Stokes shift of 50 nm or less.

4 . The color conversion film of claim 1 , wherein the organic fluorescent substance includes a first fluorescent substance and a second fluorescent substance, the color conversion film has a maximum light emission wavelength in a 590 nm to 680 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and the first fluorescent substance and the second fluorescent substance each have a different FWHM at light emission peak in a film state when irradiating light.

5 . The color conversion film of claim 1 , wherein the organic fluorescent substance is an organic fluorescent substance absorbing blue or green light and emitting red light, the organic fluorescent substance includes a first fluorescent substance and a second fluorescent substance that are different from each other, and the first fluorescent substance receives at least some of excited electrons of the second fluorescent substance, or at least some of absorption wavelengths of the first fluorescent substance are overlapped with at least some of light emission wavelengths of the second fluorescent substance.

6 . The color conversion film of claim 2 , wherein the first fluorescent substance and the second fluorescent substance each have a different FWHM at light emission wavelength in a film state when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

7 . The color conversion film of claim 6 , wherein the FWHM at light emission wavelength of the first fluorescent substance in a film state is narrower than the FWHM at light emission wavelength of the second fluorescent substance in a film state when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

8 . The color conversion film of claim 7 , wherein the FWHM at light emission wavelength of the first fluorescent substance in a film state is 60 nm or less when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

9 . The color conversion film of claim 2 , wherein the FWHM at light emission wavelength of the second fluorescent substance in a film state is 70 nm or higher.

10 . The color conversion film of claim 2 , wherein the light emission wavelength of the second fluorescent substance in a film state includes a maximum absorption wavelength of the first fluorescent substance in a film state when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

11 . The color conversion film of claim 3 , wherein the first fluorescent substance has a maximum light emission wavelength in a 620 nm to 680 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and the second fluorescent substance has a maximum light emission wavelength in a 590 nm to 630 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

12 . The color conversion film of claim 2 , wherein the color conversion film has a maximum light emission wavelength in a 590 nm to 680 nm range when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution, and the first fluorescent substance has a Stokes shift of 50 nm or less.

13 . The color conversion film of claim 2 , wherein the second fluorescent substance absorbs light with at least some of wavelengths from 450 nm to 570 nm, and a light emission wavelength includes at least some from 570 nm to 630 nm.

14 . The color conversion film of claim 2 , wherein the first fluorescent substance absorbs light with at least some of wavelengths from 570 nm to 620 nm, and a maximum light emission wavelength is 620 nm or higher.

15 . The color conversion film of claim 1 , which has a maximum light emission wavelength of 620 nm or higher.

16 . The color conversion film of claim 2 , which has a FWHM at light emission wavelength of 70 nm or less in a wavelength range selected from 600 nm to 780 nm when irradiating light having a light emission peak at 450 nm, a FWHM of 40 nm or less and monomodal light emission intensity distribution.

17 . A method for preparing the color conversion film of claim 2 , the method comprising:
coating a resin solution in which an organic fluorescent substance including a first fluorescent substance and a second fluorescent substance that are different from each other is dissolved on a substrate; and drying the resin solution coated on the substrate.

18 . The method for preparing the color conversion film of claim 2 , the method comprising extruding an organic fluorescent substance including a first fluorescent substance and a second fluorescent substance that are different from each other together with a resin.

19 . A back light unit including the color conversion film of claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Shin Dong Mok
• Ahn Byeong In
• Kim Nari
• Kim Ji Ho
• Seo Joo Yeon

Classifications

• G02B6/0055

  Reflecting element, sheet or layer · CPC title

• G02B5/201

  in the form of arrays · CPC title

• F21K9/56

  Mechanical Engineering · mapped topic

• G02B6/005 Primary

  provided by one optical element, or plurality thereof, placed on the light output side of the light guide · CPC title

• G02B5/223 Primary

  containing organic substances, e.g. dyes, inks or pigments · CPC title