KR100952647B1 - Luminescent Sheet - Google Patents

Abstract

The present invention is a transparent electrode layer formed on a substrate; In the light emitting sheet comprising a fluorescent layer, a dielectric layer, an electrode layer and a protective layer sequentially formed on the transparent electrode layer, the transparent electrode layer is selected from the group consisting of carbon nanotubes, conductive polymers, and mixtures of carbon nanotubes and conductive polymers It relates to a light emitting sheet, characterized in that any one made of a coated film form.

The light emitting sheet according to the present invention comprises a transparent electrode layer formed of a film coated with a carbon nanotube, any one selected from the group consisting of a conductive polymer, and a mixture of carbon nanotubes and a conductive polymer, the cost of the light emitting sheet compared to the conventional It can be lowered, and exhibits excellent bending or bending characteristics, thereby reducing damage to the electrode due to electrode deformation, electrode breakage, etc., and preventing damage to the fluorescent layer, thereby exhibiting improved functions. Excellent lifespan characteristics can be maintained.

Light emitting sheet, carbon nanotube, conductive polymer

Description

Luminescent Sheet

The present invention is a transparent electrode layer formed on a substrate; In the light emitting sheet comprising a fluorescent layer, a dielectric layer, an electrode layer and a protective layer sequentially formed on the transparent electrode layer, the transparent electrode layer is selected from the group consisting of carbon nanotubes, conductive polymers, and mixtures of carbon nanotubes and conductive polymers It relates to a light emitting sheet, characterized in that any one made of a coated film form.

In the 21st century, the lighting industry is taking a new leap forward as a very important industry. In particular, as various demands occur in the display industry, advertising market, lighting, etc., it is necessary to replace the BLU of LCD, or to replace sign towers, signs, or advertising devices made by fluorescent lamps of the advertising market or the corresponding general lighting fixtures. There is a need for lighting devices with new functions that replace fluorescent or equivalent bulbs, such as homes and offices.

In addition, the conventional light source devices are glass tubes or light emitting devices of small size, which overcomes the limitations in use, transportation, and installation, and needs to actively cope with the technological changes of the present time to be changed into flat and flat panel types. This has grown.

In this regard, various related efforts have been made in each related business field to develop a light emitting sheet that meets these demands, and various methods have been attempted, but the current method has not been greatly improved.

In response to such technological changes, interest in light emitting sheets is increasing, and generally, light emitting sheets are configured in a form in which a structure of a fluorescent lamp is transferred to a plane. The biggest problem is how to form the transparent electrode layer. After the transparent electrode layer is made, the structure of a general fluorescent lamp, a light bulb, or other lighting is planarized. In other words, an EL (Electro Luminescence) layer is formed by using a phosphor to emit light between the transparent electrode layers. At this time, the method of supplying electricity between the fluorescent layer, having the characteristic of emitting light to the outside while the electricity is the key. The remaining general fluorescent layer, dielectric layer, electrode layer and protective layer constituting the sheet are the same as those of the fluorescent lamp, and the fluorescent lamp structure is planarized.

In the conventional light emitting sheet, the use of ITO (Indium Tin Oxide) coated film to form a transparent electrode on the upper layer of the film was the most basic of product formation, and ITO is a display device because of the transparency and electrical conductivity of ITO. It has been used for optical sheets and light emitting sheets. However, this is very expensive, the amount of indium is very small on the earth, there is a problem that the film of ITO forms a very expensive price range.

In addition, despite the high price, the light emitting sheet manufactured based on ITO has very weak characteristics in bending and bending, and the use of the light emitting sheet is extremely limited. Not commercialization has been a problem.

Accordingly, there is a need for development of a light emitting sheet that is relatively inexpensive, exhibits improved functional characteristics and has excellent life characteristics, and which can emit light for a long time.

Accordingly, an object of the present invention is to solve the problems of the prior art as described above and the technical problems that have been requested from the past.

Specifically, it is an object of the present invention to provide a light emitting sheet having excellent lifespan characteristics by reducing breakage of an electrode or a fluorescent layer through a light emitting sheet having a low cost and flexibility.

Light emitting sheet according to the present invention for achieving this object is a transparent electrode layer formed on a substrate; A light emitting sheet comprising a fluorescent layer, a dielectric layer, an electrode layer, and a protective layer sequentially formed on the transparent electrode layer, wherein the transparent electrode layer is any selected from the group consisting of carbon nanotubes, conductive polymers, and mixtures of carbon nanotubes and conductive polymers. It consists of one in the form of a coated film.

In this case, in the light emitting sheet which is generally very important to make the electrode having transparency, do not use expensive ITO, which is a transparent material having an electrical resistance of 1000 Ω or less, which has been used in the transparent electrode layer in the past, thereby preventing cost increase of the light emitting sheet. It can exhibit excellent physical properties, especially the electrode breakage problem caused by the difference in thermal expansion coefficient between the ITO thin film and the substrate, and has a stronger adhesive strength with the binder contained in the fluorescent layer than ITO, such as bending and bending The problem caused by the lifting of the phosphor or separation between the phosphor and the transparent electrode layer can be solved.

The carbon nanotubes are not particularly limited as long as they have excellent permeability and physical properties so that they can be suitably used for the transparent electrode layer of the light emitting sheet, for example, arc discharge (see US Patent No. 5,424,054), laser vaporization ( laser evaporation: see Chem. Phys. Lett. 243, 1-12 (1995) and Science, 273: 483-487 (1996)), thermal chemical vapor deposition (CVD), catalytic synthesis (US Pat. No. 6,210,800). Reference), a plasma synthesis method, a gas phase synthesis method (see US Patent No. 6,221,330 and International Patent Publication No. 00/26138), and a liquid phase method.

In particular, the carbon nanotubes exhibit excellent permeability in the visible region of 400 nm to 750 nm, and are excellent in durability and bending resistance, and thus can solve the problem of breakage during bending frequently caused by the use of conventional ITO. In addition, the carbon nanotubes can form a uniform network, thereby inducing the formation of a uniform electrical conductivity.

The conductive polymer may be polyacetylene, polyparaphenyline (PPP), polypyrrole (PPy), polythiophene (PT), poly (3-alkyl-thiophene) (poly (3-aklylthiophene) , Polyphenylene sulfide, polyphenylenevinylene, polythienylenevinylene, polyphenylene, polyisothianaphthene (PITN), polyazulene ), Polyfuran (polyfuran) and polyaniline (polyniline (PANI)) may be any one selected from the group consisting of, preferably polyacetylene, poly paraphenylrin (PPP), polypyrrole (PPy), polythiophene (PT) ), Polyisothionaphthine (PITN) or polyaniline (PANI).

In some cases, the transparent electrode layer may include a mixture of carbon nanotubes and a conductive polymer for more stable and excellent electrical conductivity. At this time, the ratio of the carbon nanotubes and the conductive polymer included in the mixture is not particularly limited, for example, may be included in a ratio of 0.1 to 99.9: 99.9 to 0.1.

The substrate may be used differently depending on various transparent electrode layers, for example, polyethylene terephthalate (PET) film, triacetylcellulose (TAC) film, polyethylene naphthalate (PEN) film, thermal plastic polyurethane (TPU) film, and polyurethane (PU). ) Film, PC (Polycarbonate) Film, PES (Polyether Sulfone), PVA (Polyvinyl Alcohol) Film, PI (Polyimide) Film, COC (Cyclic Olefin Copolymer) Film, PVC (Polyvinyl Chloride) Film, OPP (Oriented Polypropylene) Film, Chlorinated Polypropylene (CPP) Film, Polyethylene (PE) Film, Polypropylene (PP) Film, Propylene Oxide (PO) Film, Propylene Glycol (PG) Film, Polyol (PPG; Polypropylene Glycol) Film, Polystyrene (PS) Film, Styrene Butatidene It may be composed of a series SBS, SEBS, SEP film.

The light emitting sheet has a planar structure, which forms an anode to allow electricity to flow, and forms a fluorescent layer and a dielectric layer therebetween, thereby making one layer of the light emitting sheet transparent, so that light is reflected in one direction of the plane. It is a structure.

As defined above, the transparent electrode layer of the light emitting sheet according to the present invention is formed in the form of a film coated with the carbon nanotubes or the conductive polymer.

The coating is made of a roll unit rather than a sheet unit, and is not particularly limited as long as it is a roll to roll process. However, a gravure coater, a comma coater screen printing, or a knife is used. Particularly preferred is through printing by coating, and in some cases may be by micro gravure or die coating. Through this, it is possible to form the required layer in the form of a roll continuously at a time, thereby enabling mass production.

The conventional coating process is schematically shown in FIG. 1, and referring to FIG. 1, the conventional coating process is a technique of coating through the silk screen 11, and a necessary layer must be repeatedly formed several times. , No continuous process for forming layers on the rolls 15, 16 could be made. As a result, the production volume is very low, which not only hinders the price and commercialization of the light emitting sheet 12 including the transparent electrode layer, but also one layer formed by a general process of silk screen is formed through repetitive operations of two to five times. As a result, there was a technical limitation that a very high product price was to be formed, the precision was low, the product life was very short, it was not mass produced, and there was a disadvantage that only a size of 1 m ² could be manufactured.

In contrast, FIG. 2 schematically illustrates a coating process performed by a gravure coating device, and the coating of the light emitting sheet 12 ′ including the transparent electrode layer may be formed in a continuous roll form. In other words, by solving the problems according to the prior art through the gravure coating device, it is possible to quickly mass production, to simplify the process, to lower the manufacturing cost, to exhibit an effect that significantly reduces the occurrence of defects during manufacturing. Can be.

The light emitting sheet according to the present invention sequentially includes a fluorescent layer, a dielectric layer, an electrode layer, and a protective layer in addition to the transparent electrode layer.

The phosphor layer may include an inorganic phosphor or a mixture of an organic phosphor and a binder, that is, an inorganic phosphor and a binder or an organic phosphor and a binder, and the phosphors used may be, for example, organic EL or inorganic EL, In addition, the organic EL and the inorganic EL may be a hybrid type EL in which an appropriate amount is blended.

In one preferred embodiment, the phosphor layer may include an inorganic EL, in which case ZnS is used as a host lattice of the phosphor powder, and Cu, Cl, or Various emission colors can be realized by adding Mn. In this case, the inorganic EL and the binder may be generally mixed in a 1: 2 ratio, and may be adjusted to 1: 1 and 2: 1 in some cases.

The inorganic phosphor is ZnS: Mn, ZnS: Al, ZnS: Au, ZnS: Cu, ZnS: Cl, ZnS: Au, Cu, Al, ZnS: Cu, Al, ZnS: Cu, Cl, ZnS: Tb, ZnS: SmF ₃ , ZnS: TbF ₃ , ZnS: TmF ₃ , SrS: Ce, SrS: Cu, SrS: Eu, CaS: Eu, BaS: Eu, MgS: Eu, CaF2: Eu ²⁺ , CaS: Eu ²⁺ , CaO : Eu ²⁺ , Ba2ZnS ₃ : Mn, ZnAl ₂ S ₄ : Mn, ZnGa ₂ S ₄ : Mn and Y ₂ O ₂ S: Eu, Y ₂ O ₃ S: Eu, Y ₂ SiO ₅ : Tb, Y _{2 O 3: Eu, Gd 2 O} 3: Eu, SrTiO 3: Pr, Mg, Al, CaTiO 3: Pr, Mg, Al, (Y, Gd) BO 3: Eu, ZnGa 2 O 4: Mn, SrGa 2 S ₄ : Eu, Gd ₂ O ₂ S: Tb, Y ₃ AlO ₁₂ : Tb, Y ₂ SiO ₅ : Tb, Zn ₂ SiO ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, SrA _l2 O ₄ : Eu, ZnGa ₂ O ₄ , SrGa ₂ O ₄ : Ce, Y ₂ SiO ₅ : Ce, Sr ₅ (PO ₄ ) Cl: Eu, BaMgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₄ O ₂₃ : Eu, (SrCaBaMg) ₅ (PO ₄ ) ₃ Cl : Eu, LaPO ₄ : Ce, Tb, Ca ₁₀ (PO ₄ ) ₆ FCl: Sb, Mn, CaWO ₄ , (Y, Sr) TaO ₄ : Nb, Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy, Y ₂ O ₃ : Eu ³⁺ and Y ₂ O ₂ S: Eu ³⁺ .

In another preferred embodiment, the fluorescent layer may use an organic EL, the organic EL may be an organic monomolecule (for organic electroluminescent device emitting layer using organic monomolecule) or a polymer (polymer electroluminescent device using polymer) Light emitting layer).

The organic monomolecules include Alq ₃ , Zn (PhPy) ₂ , LiPBO, Zn (Phq) ₂ , Zn (BOX) ₂ , Be (bq) ₂ , Zn (BTZ) ₂ , Zn (ODZ) ₂ , BAlq, Zn ( TDZ) ₂ , Be (5Fla) ₂ and Zn (BIZ) ₂ , and the polymer is PPP, PF, PFV, Spiro-PF, PPV (poly phenylene vinylene), PF-PPV (Poly [ (9,9-di-n-octylfluoren-2,7-diyl) -co- (1,4-vinylenephenylene)]), PF-BV-MEH (Poly [(9,9-dioctylfluoren-2,7-diyl ) -co- (1,4-diphenylene-vinylene-2-methoxy-5- {2-ethylhexyloxy} benzene)]), DMOS-PPV, MEH-CN-PPV (Poly [2-Methoxy-5- (2 ' -ethylhexyloxy) -1,4- (1-cyanovinylene) phenylene]), MEH-PPV, CN-PPV, CN-PPP-High (Poly [2- (6-Cyano-6-methylheptyloxy) -1,4-phenylene ]), PPP, DO-PPP, m-PPP and mixtures thereof.

The fluorescent layer may be formed on one surface of the transparent electrode layer, and in this case, it may be coated using a comma coater or gravure roll without using a conventional method of coating with silk screen for a rapid continuous process and stable production. In this case, the thickness of the fluorescent layer may be 1 to 120㎛, preferably about 10 to 100㎛.

The dielectric layer may be any dielectric material, and for example, barium titanate (BaTiO ₃ ), which is widely used as a dielectric for electrical components, may be used. The dielectric layer may be continuously formed on one surface of the fluorescent layer, and may be coated using a comma coater or gravure roll like the aforementioned fluorescent layer, and the thickness of the dielectric layer may be about 1 to 50 μm. .

The electrode layer is formed so as to conduct electricity through a sheet composed of a transparent electrode layer, a fluorescent layer, and a dielectric layer, and may include any one selected from the group consisting of silver paste, copper paste, and conductive carbon having excellent electrical conductivity.

The process of forming the electrode layer may be different depending on the material for forming the electrode layer, when the electrode layer comprises a silver paste or conductive carbon, it can be coated with a desired thickness by coating using a comma coater or gravure roll. have. When the electrode layer includes a copper paste, a layer may be formed by coating on nitrogen to prevent oxidation of copper, and in the case of copper paste, a very high temperature may be required to increase electrical conductivity. However, it is possible to increase the electrical conductivity by using conductive carbon, conductive polymers or carbon nanotubes, or by mixing two or more of them in a certain amount or in a proportion without using high heat.

In some cases, a protective layer may be formed on the lower electrode layer made of silver paste or a corresponding material to protect the rear surface from external impacts that may be applied to the light emitting sheet manufactured by the above-described process, and a comma A coater or gravure roll may be used to coat the light emitting sheet at one time.

Hereinafter, although described with reference to the drawings, the present invention is not limited thereto.

3 is a sectional view schematically showing the structure of a light emitting sheet according to the present invention. Referring to FIG. 3, the light emitting sheet 10 may include a substrate 1, a carbon nanotube or a conductive polymer, or a transparent electrode layer 2, a fluorescent layer 3, and a dielectric layer including a mixture of carbon nanotubes and a conductive polymer. 4), the electrode layer 5 and the protective layer 6, and each layer is sequentially coated as described.

As described above, the coating is continuously performed at a time by using a comma coater or gravure roll, and the light emitting sheet 10 including the transparent electrode layer 2 in the form of a film or a thin film prepared through the transparent electrode layer 2 A copper wire tape 7 is attached to each of the upper portions of the electrode layer 5 and welded with an electric wire.

The light emitting sheet according to the present invention comprises a transparent electrode layer formed of a film coated with a carbon nanotube, any one selected from the group consisting of a conductive polymer, and a mixture of carbon nanotubes and a conductive polymer, the cost of the light emitting sheet compared to the conventional It can be lowered, and exhibits excellent bending or bending characteristics, thereby reducing damage to the electrode due to electrode deformation, electrode breakage, etc., and preventing damage to the fluorescent layer, thereby exhibiting improved functions. Excellent lifespan characteristics can be maintained.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

1 is a schematic diagram showing a conventional coating process applying the silk screen coating apparatus;

Figure 2 is a schematic diagram showing a coating process applying the gravure coating device according to an embodiment of the present invention;

3 is a cross-sectional view showing a light emitting sheet according to an embodiment of the present invention.

Reference Description

1 board

2 transparent electrode layer

3 fluorescent layer

4 dielectric layers

5 electrode layer

6 protective layer

7 copper wire tape

11 silkscreen

12 Light emitting sheet or film

13 Hardening chamber

14 gravure roll

15 unwinding part (prepared transparent electrode layer film)

16 windings (finished light emitting sheet or film)

Claims (13)

A transparent electrode layer formed on the substrate; In the light emitting sheet comprising a fluorescent layer, a dielectric layer, an electrode layer and a protective layer sequentially formed on the transparent electrode layer, the transparent electrode layer is made of a film coated with a mixture of carbon nanotubes and a conductive polymer, The mixture is a light emitting sheet, characterized in that the ratio of the carbon nanotubes and the conductive polymer is 0.1 ~ 99.9: 99.9 ~ 0.1. The method of claim 1, wherein the carbon nanotubes are arc discharge, laser evaporation, thermal chemical vapor deposition, CVD, catalytic synthesis, plasma synthesis, laser vaporization, A light emitting sheet produced by any one selected from the group consisting of a catalytic synthesis method, a gas phase synthesis method and a liquid phase method. The method of claim 1, wherein the conductive polymer is polyacetylene, polypyrrole, polythiophene, poly (3-alkyl-thiophene) (poly (3-aklylthiophene), polyphenylene sulfide ( polyphenylene sulfide, polyphenylenevinylene, polythienylenevinylene, polyphenylene, polyisothianaphthene, polyazulene, polyfuran and Light-emitting sheet, characterized in that any one selected from the group consisting of polyaniline (polyniline). delete The light emitting sheet of claim 1, wherein the fluorescent layer is a mixture of an inorganic phosphor and a binder, or a mixture of an organic phosphor and a binder. The method of claim 5, wherein the inorganic phosphor is ZnS: Mn, ZnS: Al, ZnS: Au, ZnS: Cu, ZnS: Cl, ZnS: Au, Cu, Al, ZnS: Cu, Al, ZnS: Cu, Cl, ZnS: Tb, ZnS: SmF ₃ , ZnS: TbF ₃ , ZnS: TmF ₃ , SrS: Ce, SrS: Cu, SrS: Eu, CaS: Eu, BaS: Eu, MgS: Eu, CaF2: Eu ²⁺ , CaS : Eu ²⁺ , CaO: Eu ²⁺ , Ba2ZnS ₃ : Mn, ZnAl ₂ S ₄ : Mn, ZnGa ₂ S ₄ : Mn and Y ₂ O ₂ S: Eu, Y ₂ O ₃ S: Eu, Y ₂ SiO _{5: Tb, Y 2 O 3} : Eu, Gd 2 O 3: Eu, SrTiO 3: Pr, Mg, Al, CaTiO 3: Pr, Mg, Al, (Y, Gd) BO 3: Eu, ZnGa 2 O 4 : Mn, SrGa ₂ S ₄ : Eu, Gd ₂ O ₂ S: Tb, Y ₃ AlO ₁₂ : Tb, Y ₂ SiO ₅ : Tb, Zn ₂ SiO ₄ : Mn, BaAl ₁₂ O ₁₉ : Mn, SrA _l2 O _{4 : Eu, ZnGa 2 O 4,} SrGa 2 O 4: Ce, Y 2 SiO 5: Ce, Sr 5 (PO 4) Cl: Eu, BaMgAl 10 O 17: Eu, BaMgAl 14 O 23: Eu, (SrCaBaMg) 5 (PO ₄ ) ₃ Cl: Eu, LaPO ₄ : Ce, Tb, Ca ₁₀ (PO ₄ ) ₆ FCl: Sb, Mn, CaWO ₄ , (Y, Sr) TaO ₄ : Nb, Sr ₄ Al ₁₄ O ₂₅ : Eu , Dy, Y ₂ O ₃ : Eu ³⁺ and Y ₂ O ₂ S: Eu ³⁺ characterized in that the light emitting sheet is selected from the group consisting of. The method of claim 5, wherein the organic phosphor is Alq ₃ , Zn (PhPy) ₂ , LiPBO, Zn (Phq) ₂ , Zn (BOX) ₂ , Be (bq) ₂ , Zn (BTZ) ₂ , Zn (ODZ) ₂ , BAlq, Zn (TDZ) ₂ , Be (5Fla) ₂ and Zn (BIZ) ₂ . The method of claim 5, wherein the organic phosphor is PPP, PF, PFV, Spiro-PF, PPV (poly phenylene vinylene), PF-PPV (Poly [(9,9-di-n-octylfluoren-2,7-diyl) -co- (1,4-vinylenephenylene)]), PF-BV-MEH (Poly [(9,9-dioctylfluoren-2,7-diyl) -co- (1,4-diphenylene-vinylene-2-methoxy- 5- {2-ethylhexyloxy} benzene)]), DMOS-PPV, MEH-CN-PPV (Poly [2-Methoxy-5- (2'-ethylhexyloxy) -1,4- (1-cyanovinylene) phenylene]), MEH-PPV, CN-PPV, CN-PPP-High (Poly [2- (6-Cyano-6-methylheptyloxy) -1,4-phenylene]), PPP, DO-PPP, m-PPP and mixtures thereof Light emitting sheet, characterized in that selected from the group consisting of. The light emitting sheet of claim 1, wherein the fluorescent layer has a thickness of 1 to 100 µm. The light emitting sheet of claim 1, wherein the dielectric layer comprises barium titanate (BaTiO ₃ ). The light emitting sheet of claim 1, wherein the dielectric layer has a thickness of 1 to 50 μm. The light emitting sheet according to claim 1, wherein the electrode layer comprises any one selected from the group consisting of silver paste, copper paste, and conductive carbon. The light emitting sheet of claim 1, wherein the coating is performed by a gravure coater, a comma coater, or a knife coating.

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