KR20080112479A - Optical filter for display panel comprising impact resistant photopolymerized resin layer - Google Patents

Abstract

An optical filter for display panel including impact resistant photopolymerized resin layer capable of simplifying a manufacturing process is provided to omit a transparent layer of a separate electromagnetic wave shielding mesh by directly attaching a functional film without an adhesive. An optical filter for display panel includes a photopolymerized resin layer formed from a photopolymerized resin composite on one side of an electromagnetic wave shielding mesh layer(6). The photopolymerized resin composite comprises the followings: a photopolymerization urethanacrylateoligomer 40~70weight%; a reactive monomer containing one or more acrylate groups, methacrylate group, or vinyl group 15~50weight%; a photoinitiator 0.5~10weight%; and an antistatic agent 1~15weight%.

Description

Optical filter for display panel including impact resistant photopolymerized resin layer {OPTICAL FILTER FOR DISPLAY PANEL COMPRISING IMPACT RESISTANT PHOTOPOLYMERIZED RESIN LAYER}

1 is a cross-sectional view showing the structure of a conventional plasma display panel;

2 is a cross-sectional view showing the structure of a plasma display panel according to an embodiment of the present invention.

* Brief description of the reference numbers

1: anti-reflection layer 2: near-infrared blocking layer

3, 5, 7: Adhesive layer 4: Shock absorbing layer

6: electromagnetic wave shielding mesh layer 8: display panel body

The present invention relates to an optical filter for display panel including an impact resistant photopolymerized resin layer.

Recently, various studies have been conducted to increase the impact resistance of the plasma display along with the reduction of the panel weight of the large plasma display.

Conventionally, in order to increase the impact resistance of the plasma display, as shown in Figure 1, by applying an adhesive or adhesive (5) to the electric wave shielding mesh layer (6) bonded on one side of the display panel body (8) various kinds Resin was pre-processed in the form of a film or sheet to form and insert the shock absorbing layer 4.

Generally, thermoplastic resins or thermosetting resins have been used as such impact-relaxing layer film forming resins. In the case of using a thermoplastic resin, when the molding is processed by an extrusion method or a sheet molding method, fine bubbles are generated in the impact mitigating layer due to the characteristics of the process, and it is difficult to remove them. There is a problem that haze increases. In addition, when the thermosetting resin is used, deformation of the base film is caused by an external heat source during self-heating or self-heating when the resin is cured, and there is a disadvantage in that sufficient impact resistance cannot be secured. When the transparent thermosetting silicone is used, the impact resistance is excellent, but heat treatment is required, resulting in poor productivity and yield, as well as poor adhesiveness with an adhesive or an adhesive film to be laminated, and poor transparency, which is a basic requirement of an optical film.

Further, for example, Korean Patent Publication No. 2004-91003 discloses a method of forming a shock absorbing layer by laminating with an adhesive after forming a composite layer of silicone-based resin / polycarbonate resin / polyurethane resin as a shock absorbing layer. Japanese Laid-Open Patent Publication No. 2001-266759 discloses a method of forming a composite laminate film of polypropylene / ethylene-vinyl copolymer / polypropylene, and then laminating it with an acrylic adhesive to form a shock absorbing layer. However, when the impact mitigation layer is implemented by stacking multiple layers as in the above method, the machining process is complicated and the workability is reduced, and the entire impact mitigation layer is thickened. On the other hand, Korean Patent Publication No. 579329 discloses an optical filter including an impact mitigating layer formed of a sponge, a silicone rubber, a silicone resin, or the like. There is a problem in that the lifting phenomenon with the other film layer is large because it is large.

Accordingly, an object of the present invention is to mitigate external mechanical impact, exhibit antistatic properties to minimize foreign matter adherence and process defects in the manufacture of optical filters, as well as no bubbles generated, excellent transparency, and other functional films Display that includes an impact resistant photopolymer resin layer that can be directly coated on the electromagnetic shielding mesh layer without using an adhesive or adhesive to simplify the optical filter manufacturing process without implementing a transparent layer of the electromagnetic shielding mesh due to its excellent adhesiveness. It is to provide an optical filter for a panel.

In order to achieve the above object, the present invention is an optical filter for display panel comprising an electromagnetic wave shielding mesh layer, on one surface of the electromagnetic wave shielding mesh layer, (1) 40 to 70% by weight of a photopolymerizable urethane acrylate oligomer, (2) 15 to 50% by weight of reactive monomer containing at least one acrylate, methacrylate or vinyl group in the molecule, (3) 0.5 to 10% by weight of photoinitiator, and (4) 1 to 15% by weight of antistatic agent It provides the optical filter for display panels containing the photopolymerization resin layer formed from the photopolymerization type resin composition containing.

Hereinafter, the present invention will be described in more detail.

The photopolymerizable resin composition according to the present invention mitigates the external mechanical impact, exhibits antistatic properties, and when applied to the impact mitigating layer of the optical filter, not only minimizes foreign matter adhesion and process defects, but also does not generate bubbles. Excellent transparency and excellent adhesion with other functional films can be applied directly to the electromagnetic shielding mesh layer without the use of adhesives or adhesives to simplify the optical filter manufacturing process without implementing a transparent layer of a separate electromagnetic shielding mesh Etc. have an excellent effect.

The photopolymerizable resin composition used in the present invention includes the following components (1) to (4), which will be described in more detail below.

(1) photopolymerization urethane acrylate oligomer

The photopolymerizable urethane acrylate oligomer used in the photopolymerizable resin composition of the present invention is preferably used in an amount of 40 to 70% by weight based on the photopolymerizable resin composition. When the amount of the photopolymerizable urethane acrylate is less than 40% by weight, the curing shrinkage rate of the photopolymerizable resin composition is increased, so that the film is difficult to realize, and the transmittance is decreased. There is a problem in workability.

The photopolymerized urethane acrylate oligomer used in the present invention comprises (i) 5 to 50% by weight of polyol copolymer, (ii) 5 to 50% by weight of polyisocyanate, (iii) 15 to 40% by weight of acrylate alcohol, (iv) It may be prepared by adding 0.01 to 2.5% by weight of the urethane reaction catalyst and 0.01 to 2.5% by weight of the (v) polymerization initiator.

(i) polyol copolymer

The polyol copolymer has a weight average molecular weight (Mw) of 2,000 to 40,000 and includes a repeating unit of (-CH ₂ CH ₂ O-) m or (-CH ₂ CH (CH ₂ CH ₃ ) O-) n, At this time, m and n is preferably 1 to 1,000. Preferred examples of the polyol copolymer include polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol or ring-opening tetrahydrofuran propylene oxide air Tetrahydrofurane propyleneoxide ring opening copolymer. The polyol copolymer may optionally be used in combination with a sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, or a mixture thereof. When used in combination, for example, it is preferable to mix 50 to 90% by weight of the polyol copolymer with 10 to 50% by weight of sorbitan fatty acid ester or polyoxyethylene sorbitan fatty acid ester.

(ii) polyisocyanates

The polyisocyanate used in the present invention preferably has 1 to 3 isocyanate groups, and preferred examples thereof include 2,4-tolyenediisocyanate and 1,5-naphthalenediisocyanate (1,5- naphthalenediisocyanate), 2,6-tolylenediisocyanate, 1,3-xylenediisocyanate, 1,4-xylenediisocyanate, 1,6-hexanediisocyanate, Preference is given to those selected from the group consisting of isophoronediisocyanate (IPDI) and mixtures thereof.

(iii) acrylate alcohol

The acrylate alcohol used in the present invention preferably contains at least one (meth) acrylate and a hydroxy group, and preferred examples thereof include 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylic. Latex, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxy Butyl acrylate, neopentyl glycomono (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol penta (meth) acrylate, dipenta It is preferably selected from the group consisting of erythritol penta (meth) acrylate and mixtures thereof.

(iv) urethane reaction catalyst

The urethane reaction catalyst used in the present invention is a catalyst which is added in a small amount during the urethane reaction, and examples thereof include copper naphthenate, cobalt naphthenate, zinc naphate, n-butyltinlaurate, and tristil. It is preferably selected from the group consisting of amines (tristhylamine), 2-methyltriethylene diamide and mixtures thereof.

(v) polymerization initiator

Preferred examples of the polymerization initiator used in the present invention are selected from the group consisting of dibutyltin laurate (DBTDL), hydroquinone, hydroquinone monomethyl ether, para-benzoquinone, phenothiazine and mixtures thereof It is preferable.

The photopolymerized urethane acrylate oligomer used in the present invention can be synthesized from each of the above components as follows.

First, a polyol copolymer, optionally a mixture with a sorbitan fatty acid ester compound, and a polymerization initiator are placed in a reactor to remove moisture by vacuum decompression for 30 minutes to 1 hour, and then the mixture from which the moisture is removed is removed at 40 to 65 ° C. Hold at temperature for 30 minutes to 1 hour. Polyisocyanate was added thereto in a split form and stirred at 200 to 300 rpm, while copper naphthenate, cobalt naphthenate, zinc naphate, n-butyltinlaurate, tristhylamine or A urethane reaction catalyst, such as 2-methyltriethylenediamide, is added about 1/3 of the total amount of catalyst used and about 2 until the -OH peak disappears on the IR while maintaining the reaction temperature at 50-75 ° C. The reaction is carried out for about 3 hours. After the completion of the reaction, the acrylate alcohol was added, the temperature was raised to 60 to 80 ° C., and the remaining amount of the reactive catalyst (2/3) was added thereto, followed by reaction until the -NCO peak disappeared on the IR. Rate oligomers can be obtained.

The photopolymerized urethane acrylate oligomer obtained by the above method preferably has a weight average molecular weight in the range of about 10,000 to 150,000, and a viscosity of 1,000 to 50,000 cps (25 ° C., Brookfield Viscometer).

(2) reactive monomer

The reactive monomer used in the present invention is used to improve adhesion to the surface to be coated, and in order to match the working viscosity with the photopolymerizable urethane acrylate oligomer, it is preferable to use a low molecular weight monomer having a molecular weight of 70 to 300. It is preferable that it is 1-100 cps (25 degreeC). In addition, monomers having one or more acrylate groups, methacrylate groups or vinyl groups in the molecular structure and having 1 to 6 various functional groups can be used, and particularly those having high tensile strength and low curing shrinkage in the film state desirable.

Preferred examples of the reactive monomer used in the present invention are phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy tetraethylene glycol acrylate, phenoxy hexaethylene glycol acrylate, isobornyl acrylate (IBOA), isobonyl Methacrylate, bisphenol ethoxylate diacrylate, ethoxylate phenol monoacrylate, polyethyleneglycol 200 diacrylate, tripropyleneglycol diacrylate, trimethylpropane triacrylate (TMPTA), polyethyleneglycol Diacrylate, ethylene oxide addition triethyl propane triacrylate, pentaerythritol tetraacrylate (PETA), 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, ethoxyl Rated Pentaeris Ethoxylated pentaerythritol tetraacrylate, ethoxylated nonylphenol acrylate, 2-phenoxyethyl acrylate, ethoxylated bisphenol A diacrylate, alkoxylated nonylphenol acrylate, Alkoxylated trifunctional acrylate esters, metallic diacrylates, trifunctional acrylate esters, trifunctional methacrylate esters or mixtures thereof Etc.

The reactive monomer is preferably used in the range of 15 to 50% by weight with respect to the photopolymerizable resin composition, and when the amount is less than 15% by weight, the oligomer composite having a high viscosity is up to a working viscosity of 1,500 to 3,000 cps (25 ° C). Dilution is difficult, and when it exceeds 50% by weight, the curing shrinkage of the film increases during curing, resulting in a problem that the light transmittance is lowered by bending.

(3) photoinitiator

In the present invention, since the photoinitiator maintains a line speed of 10 to 25 m / min or more during film production, and 200 to 2,000 μm thick film coating is performed, the photoinitiator is added to maintain the fast curing speed of the resin itself and to cure to the core of the film. . The photoinitiator may receive ultraviolet energy to form free radicals and attack the double bond in the resin to induce polymerization.

As photoinitiators used in the present invention, commercially available Irgacure # 184 (Cycle Geigy) (hydroxycyclohexylphenylketone), Irgacure # 907 (2-methyl -1 [4- (methylthio) phenyl] -2-morpholino-propan-1-one) (2-methyl-1 [4- (methythio) phenyl] -2-morpholino-propan-1-on)), Irgacure # 500 (hydroxyketones and benzophoenone), Irgacure # 651 (benzildimethyl-ketone), Darocure # 1173 (2) 2-hydroxy-2-methyl-1-phenyl-propan-1-one), Darocure # 116, CGI # 1800 ( Bisacyl phosphine oxide) or CGI # 1700 (bisacyl phosphine oxide and hydroxy ketone) may be used.

(4) antistatic agent

The antistatic agent used in the present invention is used to ameliorate electrostatic problems that may occur during operation in manufacturing optical films. It is preferable that the antistatic agent does not contain water, and representative examples thereof include Morestst ES-1200, Morestst ES-1801, Morestst ES-2200, Morestst ES-2400 or more commercially available from Morechem. Nonionic amines such as Morestst ES-2300; Fatty acid esters of polyhydric alcohols of Morestst ES-1895; Fatty amides of Morestst ES-2500; Cationic quaternary ammonium salts such as Morestst ES-3000, Morestst ES-3300 or Morestst ES-6000; It is preferable to select from the group consisting of Morestst ES-6500 alkyl amine sulfate system, Celtex-ASA manufactured by Cell Chemical, and Celtex-AS7 alkyl betaine.

In addition, the photopolymerizable resin composition of the present invention may be used an effective amount of a conventional antifoaming agent, a leveling agent or an adhesion enhancer, etc. as other additives, preferably 0.1 to 1% by weight.

The photopolymerizable resin composition may be obtained by adding a conventional method, for example, a photopolymerizable urethane acrylate oligomer, a reactive monomer, a photoinitiator, and an antistatic agent in order, and stirring the solution at a uniform speed of 1000 rpm or more at a temperature of 15 to 50 ° C. have. At this time, when the reaction temperature is less than 15 ℃, the viscosity of the photopolymerized urethane acrylate oligomer rises in the process problems, if the reaction temperature exceeds 50 ℃ may initiate a curing reaction by forming a photoinitiator radicals . In addition, since side reactions in which unreacted substances react with moisture in the air may occur, the moisture in the reactor is preferably maintained at 50% or less, and for this purpose, the reaction is preferably performed under vacuum conditions.

It is preferable that the photopolymerizable resin composition of this invention manufactured by the above method has a viscosity of 200-3000 cps (25 degreeC).

The photopolymerizable resin composition may be applied onto the electromagnetic wave shielding layer using a coating machine without being pre-processed in the form of a film or a sheet, and has an advantage of not only using impact resistance but also excellent adhesiveness, so that a separate adhesive may not be used.

The optical filter for display panel according to the present invention can be produced, for example, as follows. Referring to FIG. 2, first, the photopolymerizable resin composition according to the present invention is directly applied onto the electromagnetic wave shielding mesh layer 6 without using an adhesive, and then UV cured to form the photopolymer resin layer as the impact mitigating layer 4. Next, the pressure-sensitive adhesive layer 3, the near-infrared blocking layer 2, and the anti-reflection layer 1 may be sequentially stacked on the impact mitigating layer 4 to manufacture an optical filter according to the present invention. The electromagnetic wave shielding mesh layer 6, the pressure-sensitive adhesive layer 3, and the near-infrared blocking layer 2 and the anti-reflection layer 1 serving as functional layers can be formed by a conventional method, and combinations of these configurations, the order And methods are not limited. In addition, any of the layers may be excluded or additional optical functional layers other than the above layers may be formed, such as antireflective layers, near infrared blocking layers, neon light blocking layers or color correction layers.

According to the conventional method, the optical filter according to the present invention is coated with the adhesive layer 7 on the other side of the electromagnetic wave shielding film in which the impact mitigating layer is implemented, and then attached to the glass of the display panel body 8 to display panels. Can be formed.

In the present invention, the thickness of the photopolymerized resin layer (impact mitigating layer) formed by coating directly on the electromagnetic wave shielding mesh layer is preferably 0.2 to 2 mm, and when the thickness is less than 0.2 mm, it is difficult to secure desired impact characteristics. In the case of exceeding 2 mm, the transmittance and the haze may be increased, thereby making it difficult to secure optical properties and deteriorating workability.

As described above, the optical filter formed using the photopolymerizable resin composition having a specific composition not only minimizes foreign matter adhesion and process defects, but also does not generate bubbles and has excellent transparency, and excellent adhesion with other functional films. By directly applying to the electromagnetic shielding mesh layer without using an adhesive or pressure-sensitive adhesive has an excellent effect, such as to simplify the optical filter manufacturing process without implementing a transparent layer of a separate electromagnetic shielding mesh.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

<Production of Photopolymerizable Resin Composition>

Preparation Example 1

50% by weight poly tetramethylene glycol (PTMG), 28% by weight isophorone diisocyanate (IPDI), 21% by weight 2-hydroxyethyl (meth) acrylate (2-HEMA), 0.5% by weight copper naphthenate and dibutyl 40% by weight of a photopolymerized urethane acrylate oligomer polymerized using 0.5% by weight of thylaurate (DBTDL), 50% by weight of isobonyl acrylate (IBOA) as a reactive monomer, and Igacure from Ciba Geigy as a photoinitiator. (Irgacure) # 184 5 wt% and Morestst ES-6000 5 wt% of Morechem as an antistatic agent was mixed and stirred at a uniform rate of 100rpm at a temperature of 25 ℃ to obtain a photopolymerizable resin composition.

Preparation Example 2

A photopolymerizable resin composition was obtained in the same manner as in Preparation Example 1, except that 50 wt% of the photopolymerizable urethane acrylate oligomer and 40 wt% of isobornyl acrylate (IBOA) were used as the reactive monomer.

Preparation Example 3

A photopolymerizable resin composition was obtained in the same manner as in Preparation Example 1, except that 60 wt% of the photopolymerizable urethane acrylate oligomer and 30 wt% of isobornyl acrylate (IBOA) were used as the reactive monomer.

<Manufacture of optical filter for display panel>

Example 1

Anti-reflection film: hybrid anti-reflection film (NOF, N785UV-012, thickness 150㎛)

(Anti-reflective layer 5 micrometers, PET film 100 micrometers, NIR barrier layer: 20 micrometers, adhesive layer: 25 micrometers)

-Electromagnetic shielding mesh film: Nippon Filcon 42 inches (580mm × 990mm, thickness 140㎛)

(Mesh layer: 15 µm, PET film (substrate film): 100 µm, pressure-sensitive adhesive layer: 25 µm)

-Shock absorbing layer: Coating the photopolymerizable resin composition obtained in Preparation Example 1 on the electromagnetic wave shielding mesh film, and UV curing (1200mJ, 10mpm)-Coating thickness: 300㎛

(The electromagnetic wave shielding film in which the impact mitigating layer was implemented was attached to a glass substrate (Samsung Corning soda lime glass, thickness 2.8mm × 300mm × 300mm) using an adhesive (Sokken SK-Dyne 1435 25㎛))

The antireflection film, the shock absorbing layer, and the electromagnetic wave shielding film were sequentially formed to prepare an optical filter having a total of 590 μm.

Example 2

An optical filter having a thickness of 790 μm was prepared in the same manner as in Example 1, except that the thickness of the shock absorbing layer was 500 μm.

Example 3

An optical filter having a thickness of 1,290 μm was prepared in the same manner as in Example 1, except that the impact mitigating layer had a thickness of 1,000 μm.

Example 4

An optical filter having a thickness of 790 μm was prepared in the same manner as in Example 2, except that the impact relaxation layer was formed using the photopolymerizable resin composition obtained in Preparation Example 2.

Example 5

An optical filter having a thickness of 790 μm was prepared in the same manner as in Example 2, except that the impact relaxation layer was formed using the photopolymerizable resin composition obtained in Preparation Example 3.

Comparative Example 1

100 parts by weight of a silicone resin solution (SE1885A, manufactured by Dow Corning Silicone, SE1885B) and 100 parts by weight of a silicone resin curing agent (SE1885B, manufactured by Dow Corning Silicone, Inc.) were mixed as a resin composition for the shock absorbing layer, and the coating thickness was 1000 μm. After thermosetting at 100 ° C. for 30 minutes, the acrylic pressure-sensitive adhesive of a copolymer of butyl acrylate and acrylic acid (molecular weight about 1.5 million, Tg about −25 ° C.) as a transparent adhesive on the other side of the substrate was 25 μm thick. An optical filter having a thickness of 1,290 μm was prepared in the same manner as in Example 1 except for coating with the electromagnetic wave shielding mesh layer.

Comparative Example 2

65 parts by weight of PREMINOL PML-3012 (Asahi Glass Co., Ltd., polyether-based polio), 28 parts by weight of EXCENOL EL-1030 (Asahi Glass Co., Ltd., polyether-based polio), Preminol PML-1003 (Asahi Glass) , 100 parts by weight of a polyether based polyol), 30 parts by weight of hexamethylene diisocyanate, 0.2 parts by weight of dibutyltin dilaurate, and 2 parts by weight of an antioxidant (Ciba Co., Ltd., IRGANOX 1010) were mixed to give a PET film of 100 μm. An optical filter having a thickness of 1,290 μm (please check) was prepared in the same manner as in Comparative Example 1 except that the coating layer was cured at 80 ° C. for 20 minutes to form an impact mitigating layer after coating at 1000 μm.

Comparative Example 3

An optical filter having a thickness of 1,290 μm was prepared in the same manner as in Comparative Example 1 except that a polycarbonate (Asahi Glass Co., LEXAN 8010) 1000 μm thick flat plate was used as the resin composition for the shock absorbing layer.

Test Example

(1) Antistatic test

As a result of measuring the cumulative resistance of the optical filter on the antireflection film portion of the optical filter obtained in Examples 1 to 5 and Comparative Examples 1 to 3 using a surface resistivity analyzer (model MCP-T610, manufactured by Mitsubishi Japan), 1 to 3 has a surface resistance of 1 × 10 ¹³ Ω / Sq to 1 × 10 ¹⁴ Ω / Sq, whereas the optical filter obtained in the example according to the present invention has a surface resistance of 1 × 10 ¹² Ω / Sq or less and is good. Antistatic properties are shown.

(2) impact resistance test

The electromagnetic wave shielding film specimen in which the impact mitigating layer of the optical filters obtained in Examples 1 to 5 and Comparative Examples 1 to 3 was implemented was placed on an aluminum plate (10 mm × 1000 mm × 600 mm) (thickness × length × horizontal), and then The four sides are fixed and leaned against the concrete wall, and then 0.2 J, 0.35 J, 0.50 J, 0.70 J using a spring impact hammer (MODEL F-22, manufactured by PTL, Germany) as described in the IEC (International Electrotechnical Commission) standard The impact strength was evaluated as 1.00 J. The unbreakable case was broken and the broken case was made X. Also, when the polyamide-treated weight (radius 10 mm, 250 g) specified in the electric appliance control method was dropped from the height of about 20.4 cm. 0.5 J or more; ○, less than 0.5 J;

(3) heat resistance test

The specimens of the optical filters obtained in Examples 1 to 5 and Comparative Examples 1 to 3 were placed in an oven at 80 ° C., and after 1000 hours had elapsed, the external appearance was observed compared with that before being put into the oven. (Circle) and the case where the shock absorbing film test piece peeled from the glass substrate, the case where there was no change in the appearance of an impact relaxation film was made into x when the bubble generate | occur | produced between a film and a glass substrate, or the deformation | transformation generate | occur | produced in the surface state.

(4) transmittance test

The specimens in which the impact mitigating layers according to Examples 1 to 5 and Comparative Examples 1 to 3 were formed solely on a transparent substrate were subjected to 25 ° C. using haze-gardplus (BYK-Gardner). Haze (%) and total light transmittance (%) at were measured.

(5) Surface hardness (pencil hardness)

The antireflection layer portion of the optical filter obtained in Examples 1 to 5 and Comparative Examples 1 to 3 was inclined by 45 ° to MISUBISHI Uni pencil HB or TOMBOW # 8900 HB in a pencil hardness tester, and a 1 kg load was applied to the test surface, and the direction of the pencil lead was 5 times while changing the position of the scraping of about 40mm in length at a speed of about 3mm / sec to remove the graphite of the pencil attached to the test surface with a pencil eraser lightly to investigate the fracture state of the coating film.

(6) Shore Hardness

Specimens in which the impact mitigating layers according to Examples 1 to 5 and Comparative Examples 1 to 3 were formed solely on a transparent substrate were measured according to ASTM A 956 standard using a hardness meter model name HH-401 manufactured by Mitsutoyo Corporation, Japan.

Table 1 shows the results of the physical property test.

As shown in Table 1, the optical filters for display panels of Examples 1 to 5 manufactured by using the photopolymerizable resin composition according to the present invention have no haze, transmittance, shore hardness, surface hardness, heat resistance, impact resistance, etc. without an adhesive layer. It can be seen that excellent.

In the case of using the impact resistant photopolymerizable resin composition according to the present invention as an impact mitigating layer of an optical filter, external mechanical shocks are alleviated, antistatic properties are minimized, and foreign matter adhesion and process defects are minimized, and bubbles are not generated. Because of its excellent transparency and excellent adhesion with other functional films, it can be directly coated on the electromagnetic shielding mesh layer without using adhesives or adhesives, thereby simplifying the optical filter manufacturing process without implementing the transparent layer of the electromagnetic shielding mesh. It has such an excellent effect.

Claims (13)

In the optical filter for display panel comprising an electromagnetic wave shielding mesh layer, (1) 40 to 70% by weight of a photopolymerizable urethane acrylate oligomer, (2) at least one acrylate group in a molecule, on one surface of the electromagnetic wave shielding mesh layer, A photopolymerization resin layer formed from a photopolymerizable resin composition comprising 15 to 50% by weight of a reactive monomer containing a methacrylate group or a vinyl group, (3) 0.5 to 10% by weight of a photoinitiator, and (4) 1 to 15% by weight of an antistatic agent. An optical filter for display panel, characterized in that it comprises a. The method of claim 1, The photopolymerizable urethane acrylate oligomer is (i) 5 to 50% by weight of polyol copolymer, (ii) 5 to 50% by weight of polyisocyanate, (iii) 15 to 40% by weight of acrylate alcohol, (iv) urethane reaction catalyst 0.01 To 2.5% by weight and 0.01 to 2.5% by weight of the polymerization initiator (v), wherein the optical filter for a display panel. The method of claim 2, The polyol copolymer has a weight average molecular weight of 2,000 to 40,000, (-CH ₂ CH ₂ O-) m or (-CH ₂ CH (CH ₂ CH ₃ ) O-) n (where m and n are 1 to 1,000 An optical filter for display panel, comprising a repeating unit. The method of claim 3, The polyol copolymer is a polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol and ring-opening tetrahydrofuran propylene oxide copolymer (tetrahydrofurane propyleneoxide) ring opening copolymer), an optical filter for display panel. The method of claim 4, wherein The polyol copolymer is used in admixture with sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, or a mixture thereof. . The method of claim 2, The polyisocyanate is 2,4-tolyenediisocyanate, 1,5-naphthalenediisocyanate, 2,6-tolyenediisocyanate, 1,3-xylene diisocyanate Isocyanate (1,3-xylenediisocyanate), 1,4-xylenediisocyanate, 1,6-hexanediisocyanate, isophoronediisocyanate (IPDI) and mixtures thereof An optical filter for display panel, characterized in that The method of claim 2, The acrylate alcohol is 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxyethyl acrylate, 2-hydroxy Propyl acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, neopentylglycomono (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol penta (meth) acrylate, and a mixture thereof. The method of claim 1, The reactive monomer is phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy tetraethylene glycol acrylate, phenoxy hexaethylene glycol acrylate, isobornyl acrylate (IBOA), isobornyl methacrylate, bisphenol ethoxyl Diacrylate, ethoxylate phenol monoacrylate, polyethyleneglycol 200 diacrylate, tripropylene glycol diacrylate, trimethylpropane triacrylate (TMPTA), polyethylene glycol diacrylate, ethylene oxide Ethyleneoxide-addition triethylolpropanetri acrylate, pentaerythritol tetraacrylate (PETA), 1,4-butanediol diacrylate, 1,6-hexanedioldiacrylate, ethoxylated pentaerythritol tetra Acrylate d pentaerythritol tetraacrylate, ethoxylated nonylphenol acrylate, 2-phenoxyethyl acrylate, ethoxylated bisphenol A diacrylate, alkoxylated nonylphenol acrylate, alkoxide trifunctional Characterized in that it is selected from an acrylate ester, a metallic diacrylate, a trifunctional acrylate ester, a trifunctional methacrylate ester, and mixtures thereof. The optical filter for display panels. The method of claim 1, The optical polymerization resin layer, characterized in that the photopolymerization resin layer is directly applied to one surface of the electromagnetic wave shielding mesh layer. The method of claim 1, The photopolymerization resin layer is formed with a thickness of 0.2 mm to 2 mm, the optical filter for display panel. The method of claim 1, And at least one optical functional layer selected from an antireflection layer, a near infrared ray blocking layer, a neon light blocking layer, and a color correction layer on the photopolymerization resin layer. The method of claim 1, The haze is 0.1 to 2% and the Shore hardness (D) is 60 or less, The optical filter for display panels characterized by the above-mentioned. A display panel obtained by attaching a surface opposite to the photopolymerized resin layer of the electromagnetic wave shielding mesh layer of the optical filter according to claim 1 to the display panel body.

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