KR101961034B1 - Bright enhancing film and preparing method of the same - Google Patents

Abstract

The present invention relates to a brightness enhancement film and a method of manufacturing the same, and is characterized by comprising a base film layer, a YAG base phosphor dispersed in the base film layer, a LuAG base phosphor dispersed in the base film layer, (A) a step of uniformly dispersing a YAG-base phosphor and a LuAG-base phosphor in a molten resin, followed by casting to produce a base film; and (b) Coating the dyes on one or both sides of the substrate, and drying the coating, thereby improving the brightness, color reproducibility, and physical properties of the brightness enhancement film.

Description

Brightening Enhancing Film and Preparation Method Thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brightness enhancement film and a method of manufacturing the brightness enhancement film, and more particularly, to a brightness enhancement film and a method of manufacturing the same that can improve brightness, color reproducibility and physical properties.

Recently, the display market is evolving from a large-size and high-resolution competition to a color competition, and attention is focused on manufacturing a display capable of realizing excellent color.

OLED (Organic Light-Emitting Diode), which is widely regarded as the next generation display, can achieve the color recall rate up to 100% of NTSC. However, currently used LCD shows 70% color reproduction rate It is a situation.

Accordingly, although a method using a quantum dot is applied to improve the color gamut of an LCD, there is a problem that a sealing process through a barrier film must be accompanied by inherent characteristics of quantum dots susceptible to moisture and oxygen.

On the other hand, in the LCD, a luminance enhancement film is applied in order to increase the contrast. The brightness enhancement film can be attached to a back light unit (BLU) using a light shielding tape. The reflection type polarizing film is a film in which a high refractive index layer and a low refractive index layer are alternately repeatedly laminated, and commercially available is a dual brightness enhancement film (DBEF) ) Are used.

However, since royalty is required to use DBEF, Korean affiliates are concentrating their research and development on localization of luminance enhancement film that can replace DBEF.

Therefore, if a film that can improve the luminance of LCD without using DBEF is developed, it is expected to contribute to the activation of the domestic display market.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a brightness enhancement film capable of improving luminance, color reproduction rate, and physical characteristics to replace DBEF.

As means for solving the above-mentioned technical problem,

The present invention relates to an optical film comprising a base film layer; A YAG-base phosphor dispersed in the base film layer; A LuAG-based phosphor dispersed in the base film layer; And a dye layer coated on one side or both sides of the base film layer.

In this case, the YAG-base phosphor is _{Y 3 Al 5 0 12: Ce} 3+ (YAG: Ce), Tb 3 Al 5 0 12: Ce 3+ (TAG: Ce), Ca 3 (Sc, Mg) 2 Si 3 O ₁₂ : Ce ³⁺ , Y ₃ Mg ₂ AlSi ₂ O ₁₂ : Ce ³⁺ , and the like.

In this case, the LuAG-based fluorescent material includes at least one selected from Lu ₃ Al ₅ O ₁₂ : Ce ³⁺ , Tb ₃ Al ₅ O ₁₂ : Ce ³⁺ , Lu ₂ CaMg ₂ Si ₃ O ₁₂ : Ce ³⁺ can do.

In this case, the YAG-base phosphor may be added in an amount of 10 to 40 wt% based on 100 wt% of the base film layer composition.

In this case, the LuAG-based phosphor may be added in an amount of 1 to 20 wt% based on 100 wt% of the base film layer composition.

In this case, the dye layer may absorb light having a wavelength band of at least one of 380 to 430 nm, 480 to 510 nm, and 560 to 600 nm.

In this case, the dye layer may be any one selected from the group consisting of hydroxy-benzotriazole, rhodamine (RH), squarine (SQ), and cyanine (CY) Or more.

In this case, the dye layer may contain 0.01 to 5 wt% of dye.

In this case, the thickness of the dye layer may be 0.1 to 15 mu m.

The present invention also provides a method of manufacturing a light emitting device, comprising the steps of: (a) uniformly dispersing a YAG-base phosphor and a LuAG-base phosphor in a molten resin, And (b) coating a dye on one side or both sides of the base film and drying the base film.

According to the present invention, by uniformly dispersing the YAG-base phosphor and the LuAG-base phosphor in the base film layer at a predetermined ratio, it is possible to improve the brightness and color reproduction ratio when applied to an LCD to realize excellent color, , Bending resistance, and the like.

Further, the color reproduction ratio can be further improved by additionally coating a dye on one side or both sides of the base film layer.

In addition, since the YAG-base phosphor and the LuAG-base phosphor are included in the base film itself, a separate coating process is unnecessary, thereby improving the productivity.

1 is a laminated structure of a brightness enhancement film according to the present invention,
Fig. 2 is a laminated structure showing a modified example of the brightness enhancement film shown in Fig. 1. Fig.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention.

FIG. 1 is a laminated structure of a brightness enhancement film according to the present invention, and FIG. 2 is a laminated structure showing a modified example of the brightness enhancement film shown in FIG.

1 and 2, the brightness enhancement film 100 according to the present invention includes a base film layer 110, a YAG-base phosphor 120, a LuAG-base phosphor 121, and a dye layer 130, .

The base film layer 110 is made of a conventional resin used as a film material such as PET, TAC, PC, polyimide, and acryl.

The YAG-base phosphor 120 and the LuAG-base phosphor 121 are uniformly dispersed in the base film layer 110 at a predetermined ratio for the purpose of improving brightness, color reproducibility and physical properties.

In this case, YAG-based fluorescent material 120 is _{Y 3 Al 5 0 12: Ce} 3+ (YAG: Ce), Tb 3 Al 5 0 12: Ce 3+ (TAG: Ce), Ca 3 (Sc, Mg) 2 Si ₃ O ₁₂ : Ce ³⁺ , and Y ₃ Mg ₂ AlSi ₂ O ₁₂ : Ce ³⁺ , and may include at least one selected from the group consisting of 10 to 40 wt% of 100 wt% of the base film layer 110 composition Lt; / RTI > When the content of the YAG-base phosphor 120 is less than 10 wt%, the desired brightness enhancement effect can not be exhibited. If the content is more than 40 wt%, the coating is difficult and the color reproduction rate is lowered.

The LuAG-based phosphor 121 may include at least one selected from Lu ₃ Al ₅ O ₁₂ : Ce ³⁺ , Tb ₃ Al ₅ O ₁₂ : Ce ³⁺ , Lu ₂ CaMg ₂ Si ₃ O ₁₂ : Ce ³⁺ , And is added in a proportion of 1 to 20 wt% based on 100 wt% of the base film layer 110 composition. If the content of the LuAG-based phosphor 121 is less than 1 wt%, the desired brightness enhancement effect can not be exhibited. If the content of the LuAG-based phosphor 121 is more than 20 wt%, coating is difficult and the color reproduction rate is lowered.

The dye layer 130 is coated on one or both surfaces of the base film layer 110 to obtain a clearer color reproducibility.

The dye layer 130 absorbs light in a wavelength band of at least one of 380 to 430 nm, 480 to 510 nm, and 560 to 600 nm emitted from a light source such as a blue LED when applying the LCD of the brightness enhancement film 100, A dye capable of improving the color reproduction rate is used.

Specifically, the dye layer 130 may include a hydroxy-benzotriazole type such as 4-Hydroxy-1H-benzotriazole and 2- (2-hydroxy-5-methylphenyl) benzotriazole, Rhodamine B, Rhodamine 6G Rhodamine (RH), squarine (SQ) such as 2,4-bis [4- (N, N-dibenzylamino) -2,6-dihydroxyphenyl] squaraine, cyanine such as phthalocyanine, CY) based dyes.

The dye in the dye layer 130 is added in an amount of 0.01 to 5 wt% based on the total solid content of the dye layer 130. When the content of the dye is less than 0.01 wt%, the color reproducibility is not increased, whereas when the content exceeds 5 wt%, the luminance decreases.

The thickness of the dye layer 130 is preferably 0.1 to 15 占 퐉. This is because if the thickness of the dye layer 130 is less than 0.1 탆, the color reproduction rate is insufficient when coated, and if the thickness exceeds 15 탆, the luminance decreases.

The brightness enhancement film according to the present invention has been described above. Hereinafter, a method for manufacturing a brightness enhancement film according to the present invention will be described.

First, the YAG-base phosphor 120 and the LuAG-base phosphor 121 are uniformly dispersed in a molten resin such as PET, TAC, PC, Polyimide, Acryl or the like at a ratio of 10 to 40 wt% and 1 to 20 wt% And the dye layer 130 is coated on one or both sides of the base film 110. The brightness enhancement film 100 is completed.

In this case, in the casting step, a thermoplastic chip produced through a polymerization process is melted and discharged into a die having a predetermined width to produce a sheet, followed by biaxial stretching to produce a stretched film An extruder process in which a dried thermoplastic resin chip is supplied and heated and melted and then extruded in a T-die, a T-die process in which molten resin is discharged through a slit gap to form a molten chip, Casting roll process to produce Melt Resin discharged from die by solidification and solidification to produce casting sheet form, MDO process to longitudinally stretch using casting sheet after heat is applied to roll, A TDO process for transversely stretching and thermally fixing the film, a T / U & Winder process for cutting both ends of the film and winding the product fabric, a winding process, and a packaging process.

The method for manufacturing the brightness enhancement film according to the present invention has been described above. Hereinafter, embodiments of the present invention will be described. The present invention can be understood more clearly by the following examples, which are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

First Production Example

Fabrication of phosphor layer

900 Kg of PET Chip of Mw = 40,000 g / mol prepared by the polymerization process was melted, 100 Kg of YAG fluorescent material (10 wt% relative to Resin) was precisely dispersed in the melted PET chip, And then the PET film 100M was produced through the biaxial stretching process. The specific film-forming process is as follows.

900 Kg of PET Chip produced through the polymerization process was fed and melted. 100 Kg of YAG phosphor was precisely dispersed through a high-temperature mixer and then extruded to a T-die to quantitatively extrude a molten PET chip in which a phosphor was precisely dispersed. , Melt PET Resin was discharged through a slit gap (300 μm), and Melt Resin was rapidly quenched and hardened in a casting roll to produce a casting sheet. Thereafter, heat was applied to the casting sheet at 120 ° C, and longitudinal stretching was performed using a roll primary speed (10M / min speed). The both sides of the sheet were stretched by 110% stretched with a clip and driven at a speed of 10M / Of PET film was wound up at 100M.

Preparation of dye layer

Hydroxybenzotriazole dyestuff 4-Hydroxy-1H-benzotriazole (0.1 wt%) was added to the polymer matrix and stirred for 60 minutes. In this case, a monofunctional urethane acrylate oligomer and a monofunctional monomer were used as the polymer matrix. A photoinitiator is then added to the dye and matrix mixture. As the photoinitiator, IG184, IG907, TPO, and CP4 may be added in an amount of 1 to 5 wt%. In this case, 5 wt% of IG 184 and TPO are added at a ratio of 5: 5. Finally, the prepared coating solution was applied to one side or both sides of the PET film with a Mayer Bar and irradiated for about 5 seconds using a non-electrode lamp to prepare a luminance improving film. At this time, the irradiated light amount is preferably 500 mj or less.

Example 2

890 Kg of a PET chip of Mw = 40,000 g / mol produced by a polymerization process was melted and 100 Kg of YAG fluorescent material (10 wt% of Resin) and 10 Kg of LuAG fluorescent material (1 wt% of Resin) were finely dispersed in the melted PET chip The PET film 100M was produced through a biaxially stretching process. The specific film-forming process is as follows.

890 Kg of PET Chip produced by the polymerization process was fed and melted. 100 Kg of YAG phosphor and 10 Kg of LuAG phosphor were precisely dispersed through a high-temperature mixer and then extruded in a T-die to obtain a molten PET chip in which the phosphor was precisely dispersed Melt PET Resin was discharged through a slit gap (300 μm) to form a sheet, and Melt Resin was rapidly quenched and hardened in a casting roll to produce a casting sheet. Thereafter, heat was applied to the casting sheet at 120 ° C, and longitudinal stretching was performed using a roll primary speed (10M / min speed). The both sides of the sheet were stretched by 110% stretched with a clip and driven at a speed of 10M / Of PET film was wound up at 100M. In this case, the dye layer was prepared in the same manner as in the first production example.

Third Manufacturing Example

A PET film was prepared in the same manner as in the second production example except that 850 kg of PET chip was used and the content of LuAG phosphor was adjusted to 50 Kg (5 wt% based on Resin).

Fourth Production Example

A PET film was prepared in the same manner as in the second production example except that 800 Kg PET Chip was used and the content of LuAG phosphor was adjusted to 100 Kg (10 wt% relative to Resin).

Fifth Manufacturing Example

A PET film was prepared in the same manner as in the first production example except that 800 Kg PET Chip was used and the content of YAG phosphor was adjusted to 200 Kg (20 wt% based on Resin).

Example 6

A PET film was prepared in the same manner as in the second production example except that 790 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 200 Kg (20 wt% relative to Resin).

Seventh Manufacturing Example

750 Kg PET Chip was used and the content of the YAG fluorescent substance was adjusted to 200 Kg (20 wt% relative to Resin) and the content of the LuAG fluorescent substance was adjusted to 50 Kg (5 wt% relative to Resin) To prepare a PET film.

Example 8

600 Kg PET Chip was used and the content of the YAG fluorescent substance was adjusted to 200 Kg (20 wt% relative to Resin) and the content of the LuAG fluorescent substance was adjusted to 200 Kg (20 wt% relative to Resin) To prepare a PET film.

Ninth Production Example

A PET film was prepared in the same manner as in the first production example except that a 600 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 400 Kg (40 wt% relative to Resin).

Example 10

A PET film was prepared in the same manner as in the second production example except that 590 kg of PET chip was used and the content of the YAG fluorescent material was adjusted to 400 Kg (40 wt% with respect to Resin).

Example 11

550 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 400 Kg (40 wt% with respect to Resin) and the content of the LuAG fluorescent material was adjusted to 50 Kg (5 wt% with respect to Resin) To prepare a PET film.

Example 12

500 Kg PET Chip was used and the content of the YAG fluorescent substance was adjusted to 400 Kg (40 wt% with respect to Resin) and the content of the LuAG fluorescent substance was adjusted to 100 Kg (10 wt% with respect to Resin) To prepare a PET film.

Example 13

A PET film was produced in the same manner as in the first production example except that 950 kg of PET chip was used and the content of the YAG fluorescent material was adjusted to 50 Kg (5 wt% based on Resin).

Example 14

A PET film was prepared in the same manner as in the second production example except that 940 Kg PET Chip was used and the content of YAG phosphor was adjusted to 50 Kg (5 wt% based on Resin).

Example 15

Except that a 900 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 50 Kg (5 wt% relative to Resin) and the content of the LuAG fluorescent material was adjusted to 50 Kg (5 wt% relative to Resin) To prepare a PET film.

Example 16

Except that the PET chip of 850 Kg was used and the content of the YAG fluorescent material was adjusted to 50 Kg (5 wt% based on Resin) and the content of the LuAG fluorescent material was adjusted to 100 Kg (10 wt% based on Resin) To prepare a PET film.

Example 17

A PET film was prepared in the same manner as in the first production example except that 500 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 500 Kg (50 wt% relative to Resin).

Example 18

A PET film was prepared in the same manner as in the second production example except that 490 Kg PET Chip was used and the content of YAG phosphor was adjusted to 500 Kg (50 wt% relative to Resin).

Article 19 Manufacturing Example

450 Kg PET Chip was used and the content of the YAG phosphor was adjusted to 500 Kg (50 wt% relative to Resin) and the content of the LuAG phosphor was adjusted to 50 Kg (5 wt% relative to Resin). PET film was prepared.

Example 20

400 Kg PET Chip was used and the content of the YAG phosphor was adjusted to 500 Kg (50 wt% relative to Resin) and the content of the LuAG phosphor was adjusted to 100 Kg (10 wt% relative to Resin). PET A film was prepared.

Example 21

Except that a PET chip of 895 kg was used and the content of the YAG fluorescent substance was adjusted to 100 kg (10 wt% relative to Resin) and the content of the LuAG fluorescent substance was adjusted to 5 kg (0.5 wt% relative to Resin) PET film was prepared.

Article 22 Manufacturing Example

750 Kg PET Chip was used and the content of the YAG fluorescent material was adjusted to 100 Kg (10 wt% relative to Resin) and the content of the LuAG fluorescent material was adjusted to 150 Kg (15 wt% relative to Resin). PET A film was prepared.

The following Table 1 summarizes the components and compositions of the first to twenty-second production examples.

Manufacturing example One 2 3 4 5 6 7 8 9 10 11 12 PET Chip 900 890 850 800 800 790 750 600 600 590 550 500 YAG phosphor 100 100 100 100 200 200 200 200 400 400 400 400 LuAG phosphor 10 50 100 10 50 200 10 50 100 Total
(kg) 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 Manufacturing example 13 14 15 16 17 18 19 20 21 22 PET Chip 950 940 900 850 500 490 450 400 895 750 YAG phosphor 50 50 50 50 500 500 500 500 100 100 LuAG phosphor 10 50 100 10 50 100 5 150 Total
(kg) 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000

First Embodiment

The brightness enhancement films prepared according to the first to twelfth production examples were cut into A4 size, and LCDs were manufactured using the same. Then, the brightness and color gamut were measured. The results are shown in Table 2 below. . In this case, the LCD is composed of a light source (Blue LED), a POP (Prism on Prism) film, and a liquid crystal panel, and a luminance enhancement film is disposed between the light source and the POP film. Also, the luminance was measured using a BM-7 FAST color luminance meter manufactured by Topcon Co., Ltd. of Japan.

Manufacturing example One 2 3 4 5 6 7 8 9 10 11 12 YAG: LuAG
[wt%] 10: 0 10: 1 10: 5 10:10 20: 0 20: 1 20: 5 20:20 40: 0 40: 1 40: 5 40:10 Luminance
[nit] 430 450 500 550 480 520 560 600 540 550 580 620 Color Reproducibility
[%] 81.3 81.8 82.4 82.6 82.6 82.3 82.4 82.6 81.3 81.2 81.4 81.6 - Ref. DBEF (LED TV): 430 nit (luminance), 81.6% (color reproducibility)
- Ref. DBEF (QD TV): 450nit (luminance), 100% (color reproducibility)

Comparative Example

The brightness and color reproduction ratio of the brightness enhancement films prepared in Examples 13 to 22 were measured in the same manner as in Examples, and the results are shown in Table 3 below.

Manufacturing example 13 14 15 16 17 18 19 20 21 22 YAG: LuAG
[wt%] 5: 0 5: 1 5: 5 5:10 50: 0 50: 1 50: 5 50:10 10: 0.5 10:15 Luminance
[nit] 230 280 290 330 500 510 530 540 400 560 Color Reproducibility
[%] 79.8 79.3 79.3 78.3 75.0 72.3 71.3 71.3 81.0 75.0 - Ref. DBEF (LED TV): 430 nit (luminance), 81.6% (color reproducibility)
- Ref. DBEF (QD TV): 450nit (luminance), 100% (color reproducibility)

Second Embodiment

The brightness and color reproduction rate were measured in the same manner as in Example 1 while changing the kind, content and thickness of the brightness enhancement film prepared according to the second production example. The results are shown in Tables 4 to 9 Respectively. In this case, the YAG fluorescent material and the LuAG fluorescent material were added in a ratio of 20: 2, and the thickness of the luminance improving film was set to 50 탆. The thickness of the dye layer was fixed to 0.1 탆 for measuring the luminance and color reproducibility according to the kinds and contents of the dyes, and the dye content was fixed to 0.1 wt% when the luminance and color reproduction rate were measured according to the dye layer thickness. On the other hand, the luminance data in [Table 4] to [Table 9] are values converted into% based on QD Ref. (450 nit).

100: brightness enhancement film 110: substrate film
120: YAG-base phosphor layer 121: LuAG-base phosphor
130: dye layer

Claims (10)

A base film layer;
A YAG-base phosphor dispersed in the base film layer;
A LuAG-based phosphor dispersed in the base film layer; And
A dye layer coated on one side or both sides of the base film layer;
≪ / RTI >
Wherein the YAG-base phosphor is at least one selected from the group consisting of Tb ₃ Al ₅ 0 ₁₂ : Ce ³⁺ (TAG: Ce), Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce ³⁺ , Y ₃ Mg ₂ AlSi ₂ O ₁₂ : Ce ³⁺ Wherein the LuAG-based phosphor is at least one selected from the group consisting of Lu ₃ Al ₅ O ₁₂ : Ce ³⁺ , Tb ₃ Al ₅ O ₁₂ : Ce ³⁺ , Lu ₂ CaMg ₂ Si ₃ O ₁₂ : Ce ³⁺ is contained in an amount of 1 to 20 wt%. delete delete delete delete The method according to claim 1,
Wherein the dye layer absorbs light having a wavelength band of at least one of 380 to 430 nm, 480 to 510 nm, and 560 to 600 nm. The method according to claim 1,
The dye layer may include at least one selected from the group consisting of hydroxybenzotriazole, rhodamine, squarine (SQ), and cyanine (CY) dyes. Wherein the brightness enhancement film is made of a metal. The method according to claim 1,
Wherein the dye layer contains 0.01 to 5 wt% of a dye. The method according to claim 1,
Wherein the thickness of the dye layer is 0.1 to 15 占 퐉. (a) uniformly dispersing a YAG-base phosphor and a LuAG-base phosphor in a molten resin, and then producing a base film through a casting process; And
(b) coating a dye on one side or both sides of the base film and drying;
, ≪ / RTI &
Wherein the YAG-base phosphor is at least one selected from the group consisting of Tb ₃ Al ₅ 0 ₁₂ : Ce ³⁺ (TAG: Ce), Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce ³⁺ , Y ₃ Mg ₂ AlSi ₂ O ₁₂ : Ce ³⁺ Wherein the LuAG-based phosphor is at least one selected from the group consisting of Lu ₃ Al ₅ O ₁₂ : Ce ³⁺ , Tb ₃ Al ₅ O ₁₂ : Ce ³⁺ , Lu ₂ CaMg ₂ Si ₃ O ₁₂ : Ce ³⁺ is contained in an amount of 1 to 20 wt%.

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