KR20090012192A - Plastic substrate - Google Patents

Abstract

A plastic substrate is provided to form a protective film for suppressing penetration of oxygen and moisture by a simple process at a low cost, thereby improving reliability and stability of the plastic substrate. An inorganic material layer(31) includes an inorganic material on an organic substrate(10). An organic material layer(32) includes an organic material on the inorganic material layer. The inorganic material layer and the organic material layer are formed by a wet process. The inorganic material layer is formed with the inorganic material separated from the organic material by specific gravity. An average diameter of the inorganic material layer is less than 100nm. The organic material layer includes a high polymer or a polymer polymerized from a reactive monomer or an oligomer.

Description

Plastic Substrate

The present invention relates to a flexible substrate, and more particularly to a plastic substrate having a protective film that can suppress the penetration of moisture and oxygen.

The present invention is derived from the research conducted as part of the IT new growth engine core technology development project of the Ministry of Information and Communication and the Ministry of Information and Telecommunication Research and Development. [Task Management Number: 2005-S-070-03, Title: Flexible Display )].

The flat panel display (FPD) includes a plasma display panel (PDP), a liquid crystal display (LCD), and a flat panel display using organic light emitting diodes (OLED).

Recently, the interest in the flexible device (flexible device) having the characteristic that the element is bent and the technology development accordingly has been made. Like conventional glass substrates, flat panel displays using inorganic materials do not have flexible properties and cannot produce flexible devices. However, a plastic substrate including polyethylene terephthalate (PET) and an organic material has a bending property, so that a flexible device can be implemented.

However, plastic substrates made of organic materials are vulnerable to moisture and oxygen. As such, in order to solve the problems of moisture and oxygen penetration of the plastic substrate, a method of forming an inorganic material on the plastic substrate using physical and chemical vapor deposition is generally used. However, when the vacuum deposition method is used to form a barrier layer of water and oxygen, a process time is long and a high process cost is required. In addition, when the inorganic layer is used as a barrier layer, the process is complicated because an organic layer must be additionally formed on the inorganic layer to protect the formed inorganic layer.

Embodiments of the present invention provide a plastic substrate having a protective film capable of suppressing the penetration of moisture and oxygen, and a method of forming the same.

Method of forming a plastic substrate according to the embodiments of the present invention comprises: forming a coating film by applying a mixture containing an inorganic material and an organic material on an organic substrate; And forming a protective film including an inorganic material layer and an organic material layer from the coating film.

A plastic substrate according to embodiments of the present invention includes: an inorganic layer on an organic substrate; And an organic material layer on the inorganic material layer. The inorganic material layer and the organic material layer are formed by a wet process.

According to an embodiment of the present invention, a protective film that can suppress the penetration of moisture and oxygen in a simple process of low cost can be formed.

According to the embodiment of the present invention, the penetration of moisture and oxygen is suppressed by the protective film provided on the plastic substrate, thereby improving the stability and reliability of the plastic substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and to fully convey the spirit of the present invention to those skilled in the art.

Although terms such as first and second are used herein to describe various elements, the elements should not be limited by such terms. These terms are only used to distinguish the elements from one another. In addition, when it is mentioned that a film is on another film or substrate, it means that it may be formed directly on another film or substrate or a third film may be interposed therebetween. In the drawings, the thickness or the like of the film or regions may be exaggerated for clarity. In the drawings, the size of elements, or the relative sizes between elements, may be somewhat exaggerated for a clearer understanding of the present invention. In addition, the shape of the elements shown in the drawings may be somewhat changed by variations in the manufacturing process. Accordingly, the embodiments disclosed herein are not to be limited to the shapes shown in the drawings unless specifically stated, it should be understood to include some modification.

1 to 3, a plastic substrate and a method of forming the same according to an embodiment of the present invention will be described.

Referring to FIG. 1, a coating film 25 is formed by applying a mixture 20 on an organic substrate 10. The mixture 20 can be applied by performing a wet process. The wet process may include bar coating, spin coating or dip coating.

The organic substrate 10 is polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polycarbonate (PC), polyimide (PI) ), Polyether sulfone (PES), polyarylite (polyarylite) and cyclic olefin copolymer (cyclic olefin copolymer, COC) may include at least one.

The mixture 20 may include an inorganic material 21 and a dispersion medium 22 surrounding the inorganic material. The dispersion medium 22 may include an organic material and a solvent. The organic material may include a high molecular polymer, a reactive monomer, or an oligomer. However, when the organic material is the reactive monomer or the oligomer, the dispersion medium 22 may not include a solvent. In addition, the dispersion medium 22 may include a polymerization initiator for inducing a polymerization reaction of the reactive monomer or the oligomer. The solvent may be an organic solvent capable of dissolving the organic material.

The inorganic material 21 may be a material having high visible light transmittance. For example, the inorganic material 21 may be silicon oxide, titanium oxide, silicon nitride, silicon, smectite, kaolinite, dickite, nacrite, halloysite, antigo Antigorite, chrysotile, pyrophyllite, montmorillonite, hectorite, tetrasilic mica, sodium teniolite, dolomite, pearl mica, talc, vermiculite ), Gold mica, zansopyrite, and at least one of chlorite.

The inorganic material 21 may have an average particle diameter smaller than the wavelength of visible light (400 to 700 nm). For example, the average particle diameter of the inorganic material 21 may be 100 nm or less, preferably 50 nm or less. In addition, the weight percentage of the inorganic material 21 in the mixture 20 may be 5 ~ 90wt%, preferably 10 ~ 80wt%. When the weight percentage of the inorganic material 21 is less than 5wt%, the inorganic material layer may not be properly formed, and when the weight percentage of the inorganic material 21 exceeds 90wt%, the inorganic material 21 may not be smoothly dispersed in the mixture 20. The reliability of the protective film may be lowered.

The polymer may include at least one of an amide resin, an acrylic resin, a cellulose resin, a halogen-containing resin, and a hydrogen bond resin. The polymer is a low density polyethylene, high density polyethylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-norbornene copolymer, ethylene-dmon copolymer, polypropylene , Ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, polyester (nylon-6, nylon-6,6, metaxylenediamine-adipic acid condensate), polymethylmethacrylimide, poly Methyl methacrylate, polystyrene, styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene copolymer, cellulose triacetate, diacetic cellulose, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polytetraflu Orethylene, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, cellulose derivative, polycarbonate, poly It may include at least any one of a sulfone, polyether sulfone, polyether ether ketone, polyphenylene oxide, polymethylene oxide, polyimide, polyarylate and polysiloxane.

The reactive monomer or the oligomer may include at least one of an acrylic hydrocarbon, an aromatic hydrocarbon, an acrylonitrile-based, and a fluoride (Cl) -based hydrocarbon. The reactive monomer or oligomer may be triethylopropane triacrylate (TEPTA), tripropylene glycol diacrylate (TPGDA), or pentaerithritol triacrylate. , PETA), Trimethylolpropane Ethoxylate Triacrylate (TMPEOTA), Methyl Methacrylate (MMA), Methacrylate (MA), Tripropylene Glycol Glycerate Diacrylate (Tri (propylene glycol) Glycerolate Diacrylate, TPGGDA), Vinyl acrylate (Vinylacrylate, VA), Styrene (ST), Divinyl Benzene (DVB), Acrylonitrile, AN ), Vinylidene chloride (VDC), vinylbenzyl chloride (VBC), vinyl stearate (Vinyl Stearate, VS), vinyl propionate (Vinyl Propionate, VP), and may include at least one of polyfunctional siloxane (siloxane) and polyfunctional silicon (silicone).

The polymerization initiator may include at least one of a photo initiator, a thermal initiator, a redox initiator, and an acid initiator. The photoinitiator 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 907), 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropane -1-one (2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropane-1-one, Irgacure 184C), 2-hydroxy-2-methyl-1-phenyl-propan-1-one ( 1-Hydroxy-2-methyl-1-phenyl-propane-1-one, Darocur 1173), mixed initiator of Irgacure 184C and benzophenone (Irgacure 500), mixed of Iragacure 184C and Iracureure 1173 Initiator (Irgacure 1000), 2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl] -2-methyl-1-propanone (2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl] -2-methyl-1propanone, Irgacure 2959), methylbenzoylformate (Darocur MBF), α, α-dimethoxy-alpha-phenylacetophenone (α, α-dimethoxy-α-phenylacetophenone, Irgacure 651 ), 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone (2-benzyl-2- (dimethylamino) -1- [4- (morpholinyl) phenyl] -1-but anone, Irgacure 369), a mixed initiator of Iragacure 369 and Iragacure 651 (Irgacure 1300), diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide (diphenyl (2,4,6-trimethylbenzoyl) -phosphine oxide, Darocur TPO), mixed initiator of Darocure TPO and Darocure 1173 (Darocur 4265), phosphine oxide, phenyl bis (2,4,6, -trimethyl benzoyl) (phenyl bis (2, 4,6-trimethyl benzoyl), Irgacure 819), mixed initiator of Iragacure 819 and Tarocure 1173 (Irgacure 2005), mixed initiator of Iragacure 819 and Tarocure 1173 (Irgacure 2010), Iragacure 819 and Taro Mixed initiator (Irgacure 2020), bis (eta 5-2,4, -cyclopetadien-1-yl) bis [2,6-difluoroor-3- (1H-pyrrole-1-yl) of Cure 1173 ) Phenyl] titanium (bis (.eta.5-2,4-cyclopentadien-1-yl) bis [2,6-difluoro-3- (1H-pyrrol-1-yl) phenyl] titanium, Irgacure 784) and benzo At least one of the mixed initiators containing phenone (HSP 188) The thermal initiators are benzoyl peroxide (BP), acetyl peroxide (AP), diauryl peroxide (DP), di-tert-butyl peroxide (di-tert- butyl peroxide (t-BTP), cumyl hydroperoxide (CHP), hydrogen peroxide (HP), potassium peroxide (PP), 2,2'-azobisisobutyl Nitrile and (2,2'-azobisisobutyronitrile, AIBN), and at least one of an azocompound, and the redox initiator may include at least one of silver alkyls and persulfate (K2S2O8). It may include.

 Referring to FIG. 2, when a predetermined time elapses, the inorganic material 21 precipitates due to the difference in specific gravity between the inorganic material 21 and the dispersion medium 22, and accumulates on the surface of the organic substrate 10. That is, the lower portion of the coating layer 25 mainly includes the inorganic material 21, and the upper portion mainly includes the dispersion medium 22.

Referring to FIG. 3, the passivation layer 30 including the inorganic layer 31 and the organic layer 32 is formed on the organic substrate 10. The inorganic layer 31 may be formed by accumulating the inorganic material 21 on the surface of the organic substrate 10 due to the difference in specific gravity. At this time, some organic material may remain between the inorganic material 21, whereby the inorganic material layer 31 may include a small amount of organic material.

The organic layer 32 may be formed by removing an organic material on the inorganic layer 31 by removing a solvent included in the dispersion medium 22. Removing the solvent may be performed by heating the dispersion medium 22. For example, the heating temperature may be 120 ~ 150 ℃.

In addition, the organic layer 32 may be formed through a polymerization reaction in which a reactive monomer or oligomer in the dispersion medium 22 is induced by a polymerization initiator. For example, the organic layer 32 may be formed by polymerizing a radical formed from a reactive monomer or oligomer by the polymerization initiator with another reactive monomer or oligomer. As described above, the inorganic material layer 31 and the organic material layer 32 may be formed at substantially the same time.

The thickness of the protective film 30 may be 0.1 μm or more, preferably 1 μm or more. In addition, the protective film 30 may further include additives such as an ultraviolet stabilizer, an antioxidant, an antistatic agent, and the like.

4, a modification of the plastic substrate according to the embodiment of the present invention will be described. Another passivation layer 40 may be formed on the organic substrate 10 having the passivation layer 30 shown in FIG. 3. That is, the plastic substrate according to the present invention may include two or more laminated protective films. The passivation layer 40 may be formed in the same manner as the above-described embodiment, and may include an inorganic layer 41 and an organic layer 42.

So far, specific embodiments of the present invention have been described. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

1 to 3 are cross-sectional views of a plastic substrate for explaining a plastic substrate and a method of forming the same according to an embodiment of the present invention.

Figure 4 is a cross-sectional view of a plastic substrate showing a modification of the plastic substrate according to an embodiment of the present invention.

♧ Explanation of Reference Numbers for Main Parts of Drawing

10 organic substrate 20 mixture

21: mineral 22: dispersion medium

25: coating film 30, 40: protective film

31, 41: inorganic layer 32, 42: organic layer

Claims (5)

An inorganic layer including an inorganic material on the organic substrate; And Including an organic material layer containing an organic material on the inorganic material layer, The inorganic material layer and the organic material layer is formed by a wet process, the inorganic material layer is formed of the inorganic material separated from the organic material by specific gravity. The method of claim 1, The inorganic layer is silicon oxide, titanium oxide, silicon nitride, silicon, smectite, kaolinite, dickite, nacrite, halloysite, antigorite, antigorite, Chrysotile, pyrophyllite, montmorillonite, hectorite, tetrasilic mica, sodium teniolite, dolomite, mother-of-pearl, talc, vermiculite, gold mica, Plastic substrate, characterized in that it comprises at least one of residual phyrite and chlorite. The method of claim 1, Plastic substrate, characterized in that the average particle diameter of the inorganic layer is 100nm or less. The method of claim 1, The organic material layer is a plastic substrate, characterized in that it comprises a polymer containing a polymer or polymerized from a reactive monomer or oligomer. The method of claim 1, The organic substrate is polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polycarbonate (PC), polyimide (PI), A plastic substrate comprising at least one of polyether sulfone (PES), polyarylite and cyclic olefin copolymer (COC).

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