KR101284958B1 - A multi-layer plastic substrate having good dimensional stability and gas barrier properties and method for preparing the same - Google Patents

Abstract

The present invention relates to a plastic substrate having a multi-layered structure having an excellent surface hardness by dramatically improving the performance of the surface coating layer and a method of manufacturing the same.

Since the plastic substrate of the multi-layered structure of the present invention simultaneously satisfies the characteristics of small linear expansion coefficient, dimensional stability, gas barrier property and surface hardness, it can be used as a plastic substrate for display devices or solar cells, and has excellent gas barrier property and surface hardness. It can also be usefully used as the material of the packaging material and the container required.

Multi-layer structure, inorganic hard coating layer, plastic substrate

Description

A multi-layered plastic substrate with excellent dimensional stability and gas barrier properties and a method of manufacturing the same {A MULTI-LAYER PLASTIC SUBSTRATE HAVING GOOD DIMENSIONAL STABILITY AND GAS BARRIER PROPERTIES AND METHOD FOR PREPARING THE SAME}

The present invention relates to a multi-layered plastic substrate and a method for manufacturing the same, and more particularly, to a multi-layered plastic substrate and a method for manufacturing the same, which satisfies characteristics such as small coefficient of linear expansion, dimensional stability, gas barrier property and surface hardness. It is about.

Glass substrates used in displays, frames, crafts and containers have many advantages such as small coefficient of linear expansion, excellent gas barrier properties, high light transmittance, surface flatness, excellent heat resistance and chemical resistance, but they are fragile and impact-resistant. There is a heavy disadvantage due to the high.

Recently, as interest in liquid crystals, organic light emitting diode displays, and electronic papers is rapidly increasing, studies are being actively conducted to replace the substrates of these display devices from glass to plastic. In other words, replacing the glass substrate with a plastic substrate may reduce the overall weight of the display device and provide design flexibility, and may be economical compared to the glass substrate when manufactured in a continuous process against impact.

On the other hand, the plastic film for use as a substrate of the display device has a process temperature of the transistor element, a high glass transition temperature that can withstand the deposition temperature of the transparent electrode, oxygen and water vapor barrier properties to prevent aging of the liquid crystal and organic light emitting material, Small coefficient of linear expansion and dimensional stability to prevent substrate warpage due to process temperature changes, high mechanical strength compatible with process equipment used in conventional glass substrates, chemical resistance to etch process, high light transmittance and low wear Characteristics such as refractive index and scratch resistance of the surface are required.

However, since there is no high functional polymer base film (including a polymer film and a polymer-inorganic composite film) satisfying all of these conditions, efforts have been made to satisfy the above properties by coating various functional layers on the polymer base film. Examples of the typical functional layer include an organic planarization layer that reduces defects on the surface of the polymer and gives flatness, a gas barrier layer made of an inorganic material for blocking gases such as oxygen and water vapor, a hard coating layer for imparting scratch resistance to the surface, and the like. . Many conventional multilayer plastic substrates have a process of coating an inorganic gas barrier layer on a polymer substrate and a hard coating layer on the gas barrier layer. A problem in manufacturing the multilayer structure is that the polymer substrate and the gas barrier layer Deformation of the polymer substrate and cracking and peeling of the inorganic thin film may occur due to a large difference in coefficient of expansion. Therefore, it can be said that the adhesion between the coating layer and the design of an appropriate multilayer structure that can minimize the stress at the interface of each layer is very important.

Vitex Systems Co., Ltd. forms a monomer thin film on a polymer substrate film, polymerizes (solidifies an organic layer) by polymerization by irradiating ultraviolet (UV) light, and forms an inorganic thin film thereon by a sputtering method thereon. The process was repeated to prepare a plurality of organic-inorganic layers, to prepare a flexible substrate having excellent gas barrier properties. However, although a product having excellent gas barrier properties can be obtained by the above method, it is not suitable for the use of a display requiring a low linear expansion coefficient, and no solution has been proposed.

In addition, US Pat. No. 6,465,953 proposes a method for dispersing getter particles that can react with incoming oxygen and water vapor in a plastic substrate in order to use the plastic substrate in an organic light emitting device sensitive to oxygen and water vapor. The size of the getter particles should be sufficiently smaller than the size of the characteristic wavelength to be emitted and evenly distributed so that the emitted light can pass through the substrate without being scattered. In addition, the method was intended to minimize the amount of oxygen and water vapor introduced by coating a gas barrier film made of an inorganic material on the plastic substrate. However, the method is difficult to produce a substrate by uniformly dispersing nanoparticles of 100 to 200 nm in size, and the thickness of the plastic substrate must be thick to contain a large amount of getter particles that can react with oxygen and water vapor. Since the barrier film is directly coated, there is a high possibility that cracks or peeling will occur on the gas barrier film due to temperature changes.

U.S. Patent No. 6,322,860 discloses a crosslinkable composition comprising a silica particle or the like on one or both sides of a polyglutamide sheet within 1 mm thickness prepared by reaction extrusion (polyfunctional acrylate monomer or oligomer, Alkoxysilane and mixtures thereof) and then photocuring or thermosetting to prepare a crosslinked coating film, coating a gas barrier film thereon, and then optionally coating the crosslinking coating film on the barrier film to provide a plastic substrate for a display device. It was prepared. However, the method is only small enough that the oxygen and water vapor transmission rates can be used in liquid crystal displays in some special cases, and still does not improve on the low linear expansion coefficient and excellent dimensional stability required for use as a substrate for glass replacement. Did.

U.S. Patent No. 6,503,634 discloses an organic-inorganic hybrid ORMOCER and a silicon oxide layer coated on one polymer substrate or on the middle layer of two polymer substrates to coat 1/30 or less of the polymer substrate prior to the oxygen permeability coating and the water vapor transmission rate. A multilayer film of 1/40 or less of the previous polymer substrate was presented. While the method has shown that oxygen and water vapor transmission rates are considerably reduced compared to the polymer substrate before coating, it can be used as a packaging material, but there is no mention of improving the coefficient of linear expansion and dimensional stability.

An object of the present invention is to provide a multi-layered plastic substrate having a low coefficient of linear expansion and excellent dimensional stability, gas barrier properties, surface hardness, and the like, compared to a conventional plastic substrate to which an organic coating layer is applied.

In addition, an object of the present invention is to provide a manufacturing method of a plastic substrate having a multi-layer structure that can be used as a packaging material and a container material of various applications that require gas barrier properties and excellent surface hardness in addition to the substrate of a display device or a solar cell.

In order to achieve the above object, the present invention provides a multi-layered plastic substrate in which an organic or organic-inorganic hybrid buffer layer, a gas barrier layer and an inorganic hard coating layer to which inorganic particles are added are sequentially stacked on a plastic film.

In addition,

a) coating and curing a sol buffer composition on one side of the plastic film to form an organic or organic-inorganic hybrid buffer layer,

b) coating an inorganic material on the organic or organic-inorganic hybrid buffer layer to form a gas barrier layer; and

c) coating and thermosetting the sol buffer composition to which the inorganic particles are added on the gas barrier layer to form an inorganic hard coating layer.

It provides a method of manufacturing a plastic substrate of a multi-layer structure comprising a.

In addition, the present invention provides a multi-layered plastic substrate having a symmetrical structure around the film by bonding the surfaces of the plastic film is not formed with a multi-layer film of the plastic substrate of the multi-layer structure.

In addition, the present invention provides a display device or a solar cell including the plastic substrate of the multi-layer structure.

The present invention also provides a packaging material or container including a plastic substrate of a multi-layer structure.

As described above, the multi-layered plastic substrate of the present invention satisfies small linear expansion coefficient, gas barrier property, dimensional stability and surface hardness at the same time, so it can be used as a plastic substrate for display device instead of glass substrate. It can be very usefully used as a material for packaging materials and containers requiring surface hardness.

The present invention is to secure a low linear expansion coefficient, excellent dimensional stability, excellent gas barrier properties and excellent surface hardness at the same time to manufacture a plastic substrate having a multi-layer structure that can replace the glass substrate having a fragile and heavy disadvantages mainly used in display devices and the like Provide a method.

In the multi-layered plastic substrate of the present invention, an organic or organic-inorganic hybrid buffer layer may be disposed between the plastic film and the gas barrier layer to minimize the difference between the coefficients of linear expansion between layers and to improve the adhesion between the layers.

The plastic substrate of the multilayer structure of the present invention can improve the hardness and dimensional stability of the surface of the substrate by placing an inorganic hard coating layer containing inorganic particles on the gas barrier layer.

The plastic substrate of the multi-layered structure of the present invention is characterized by a multi-layered structure, and without any one of these layers, the above-described layers are essentially included.

In addition, the plastic substrate of the multi-layered structure of the present invention has a symmetrical structure so that the plastic substrate does not bend in one direction according to the temperature change.

The manufacturing method of the multi-layered plastic substrate constituting the symmetrical structure can increase the productivity by using a simple process of laminating the plastic films with each other, and the small linear expansion coefficient, excellent dimensional stability, gas barrier property and excellent surface even with low-cost equipment Plastic substrates having hardness can be produced.

The plastic substrate of the multilayer structure of this invention is demonstrated in detail with reference to drawings. 1 is a cross-sectional view of a plastic substrate having a multilayer structure of the present invention, and FIG. 2 is a cross-sectional view of a plastic substrate having a multilayer structure having a symmetry by bonding the plastic substrate of the multilayer structure of the present invention.

More specifically, the multi-layered plastic substrate includes an organic or organic-inorganic hybrid buffer layer 115, a gas barrier layer 120, and inorganic particles on the plastic substrate 110 of the present invention as shown in FIG. 1. It is made by sequentially stacking the inorganic hard coating layer 125. 1, a plastic substrate having a symmetrical structure, as shown in FIG. 2, is bonded to each other using adhesives 130 of plastics on which the multilayer structure of the multilayered plastic substrate shown in FIG. 1 is not formed. can do.

The organic or organic-inorganic hybrid buffer layer serves to alleviate the difference in the large linear expansion coefficient between the plastic film and the gas barrier layer, and to improve the adhesion between the plastic film and the gas barrier layer by appropriately adjusting the composition of the organic and inorganic materials.

In addition, the organic or organic-inorganic hybrid buffer layer may planarize the surface of the plastic film, thereby minimizing defects occurring during deposition of the gas barrier layer.

At this time, the organic or organic-inorganic hybrid buffer layer is formed from the partial hydrolyzate of the buffer composition containing the organosilane and the metal alkoxide has the above-described effect.

The gas barrier layer is a high density inorganic layer having a small coefficient of linear expansion, and can block gases such as oxygen and water vapor.

The inorganic hard coating layer to which the inorganic particles are added may improve hardness and dimensional stability of the substrate surface.

In the buffer layer to which the inorganic particles are added, the inorganic particles have the above-mentioned effect by more densely promoting the curing of the buffer layer and reducing the dimensional change with respect to heat by the inorganic particles serving as a vertex of physical crosslinking.

The plastic film used in the present invention may be selected from the group consisting of a single polymer, at least one polymer blend, and a polymer composite material containing an organic or inorganic additive. When the plastic substrate of the present invention is used as a substrate of a liquid crystal display device, it is required that the polymer have high heat resistance to withstand such high temperature since the manufacturing process for forming the thin film transistor and the transparent electrode is performed at a high temperature of 200 ° C or higher. do. Examples of the polymer having such a property include polynorbornene, aromatic florene polyester, polythersulfone, bisphenol A polysulfone or polyimide. In addition, as the recent research on lowering the temperature of the high temperature substrate process proceeds, polymers such as polyethylene terephthalate, polyethylene naphthalene, polyarylate, polycarbonate or cyclic olefin copolymer which can be used up to a temperature of around 150 ° C can be used. have.

In addition, the present invention may use a plastic film in which nanomaterials are dispersed in a polymer. Such polymer composite materials include polymer-clay nanocomposites, which have a small amount of clay compared to conventional composites such as glass fibers due to the small particle size of clay (<1 micron) and the large aspect ratio. Physical properties such as mechanical properties, heat resistance, gas barrier properties, and numerical stability can be improved. That is, in order to improve the physical properties, it is important to peel off the clay layer of the layer structure and disperse it well in the polymer matrix, and satisfying this is the polymer-clay composite. Polymers that can be used in the polymer-clay composite include polystyrene, polymethacrylate, polyethylene terephthalate, polyethylene naphthalene, polyarylate, polycarbonate, cyclic olefin copolymer, polynorbornene, aromatic florene polyester , Polyisulfone, polyimide, epoxy resin or polyfunctional acrylate, and the like, and laponite, montmorillonite or megadite may be used as the clay.

In the multilayer plastic substrate of the present invention, the plastic film is preferably in the form of a film or sheet having a thickness of 10 to 1000 μm. The plastic film may be manufactured through a solution casting method or a film extrusion process, and may be briefly annealed for a few seconds to several minutes near the glass transition temperature in order to minimize deformation due to temperature after the production. After annealing, primer coating may be applied to the surface of the plastic film to improve the coating property and adhesion, or surface treatment may be performed by plasma treatment using corona, oxygen or carbon dioxide, ultraviolet-ozone treatment, or ion beam treatment with a reaction gas. have.

The buffer composition for forming the organic or organic-inorganic hybrid buffer layer includes an organosilane and a metal alkoxide, and may further include an appropriate filler, a solvent and a polymerization catalyst.

The organosilane may be used by selecting one or more from the group consisting of the compound represented by the following formula (1), wherein at least one organosilane compound should be crosslinkable.

[Formula 1]

(R ¹ ) _m -Si-X _(4-m)

Wherein X may be the same or different from each other, and hydrogen, halogen, alkoxy having 1 to 12 carbon atoms, acyloxy, alkylcarbonyl, alkoxycarbonyl, or -N (R ² ) ₂ , wherein R ² is H, or Alkyl having 1 to 12 carbon atoms), R ¹ may be the same as or different from each other, alkyl having 1 to 12 carbon atoms, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalky Nyl, alkynylaryl, halogen, substituted amino, amide, aldehyde, keto, alkylcarbonyl, carboxy, mercapto, cyano, hydroxy, alkoxy having 1 to 12 carbon atoms, alkoxycarbonyl having 1 to 12 carbon atoms, sulfur Carboxylic acid, phosphoric acid, acryloxy, methacryloxy, epoxy or vinyl group, wherein oxygen or —NR ² (wherein R ² is H or alkyl having 1 to 12 carbon atoms) is inserted between the radicals R ¹ and Si-( _{^{R 1) m -O-Si-}} X (4-m) or _{^{(R 1) m -NR 2 -Si}} -X (4-m) may be in, and m is 1 in 3 is a constant.

Examples of the organosilane include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxy Silane, phenyldimethoxysilane, phenyldiethoxysilane, methyldimethoxysilane, methyldiethoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, trimethylmethoxysilane, trimethylethoxysilane, triphenylmethoxysilane, Triphenylethoxysilane, phenyldimethylmethoxysilane, phenyldimethylethoxysilane, diphenylmethylmethoxysilane, diphenylmethylethoxysilane, dimethylmethoxysilane, dimethylethoxysilane, diphenylmethoxysilane, diphenyl Ethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, p-aminophenylsilane, allyltrimethoxysilane, n- (2-aminoethyl) -3-aminopropyltri Methoxysilane, 3-a Propyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyldiisopropylethoxysilane, (3-glycidoxypropyl) methyldiethoxysilane, 3-glycidoxypropyltrimethoxy Silane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyl Trimethoxysilane, n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane and the like.

The metal alkoxide may be used by selecting one or more from the group consisting of compounds represented by the following formula (2).

[Formula 2]

M- (R ³⁾ _z

In the formula, M represents a metal selected from the group consisting of aluminum, zirconium, and titanium, R ³ may be the same or different from each other, halogen, alkyl, alkoxy, acyloxy, or hydroxy group of 1 to 12 carbon atoms , Z is an integer of 3 or 4.

The fillers are metal, glass powder, diamond powder, silicon oxide (SiOx, where x is an integer of 2-4), clay (bentonite, smectite, kaolin, etc.), calcium phosphate, magnesium phosphate, barium sulfate, aluminum fluoride, One or more types of materials, such as calcium silicate, magnesium silicate, barium silicate, barium carbonate, barium hydroxide, aluminum silicate, can be selected and used.

The solvent may be a solvent used in a conventional partial hydrolysis reaction, preferably distilled water may be used. The catalyst is also not particularly limited, but preferably aluminum butoxide and zirconium propoxide can be used.

The amount of the filler, the solvent and the catalyst to be used is not particularly limited as added as needed.

The content of the organosilane in the buffer composition is preferably 20 to 99.99% by weight, more preferably 50 to 99% by weight, still more preferably 70 to 99% by weight. In addition, the content of the metal alkoxide may be used in 0.01 to 80% by weight, more preferably less than 70% by weight, more preferably less than 20% by weight.

In the present invention, the surface flatness Ra (Average surface roughness) of the organic or organic-inorganic hybrid buffer layer is very important. If the buffer layer is not flat, defects occur when the barrier layer is deposited, resulting in poor barrier properties. . The lower the flatness value of the surface, the higher the barrier property. In the present invention, the surface flatness of the organic or organic-inorganic hybrid buffer layer is preferably about 1 nm, more preferably within 1 nm. Specifically, the flatness may have a Ra value of 0.1 to 1.2.

When the inorganic gas barrier layer is laminated on the thus prepared buffer layer, the adhesion between the inorganic layer and the organic or organic-inorganic hybrid buffer layer is excellent, the gas barrier property is improved by the inorganic layer, the modulus of the inorganic layer itself is high, and the coefficient of linear expansion is small. Therefore, the mechanical properties of the entire substrate can also be improved.

In the method of forming the gas barrier layer, since the oxygen permeability and the water vapor permeability of the plastic film itself generally have values of several tens to thousands of units, a thin or thin metal thin film having a high density of transparent inorganic material or nanometers is physically or chemically formed on the polymer film. The method of vapor deposition coating to block oxygen and water vapor may be used. In this case, in the case of a transparent inorganic oxide thin film, defects such as pinholes or cracks are difficult to obtain sufficient oxygen and water vapor blocking effects, and in the case of thin metal thin films, it is difficult to obtain a uniform thin film having a few nanometers of thickness without visible defects as well as visible light. The light transmittance of the region is difficult to exceed 80%. The thickness of the gas barrier layer formed through the method is 5 to 1000 nm, preferably 20 to 500 nm, more preferably 50 to 200 nm.

The inorganic material may be at least one selected from the group consisting of SiO _x (where x is an integer of 1 to 4), SiO _x N _y (where x and y are each an integer of 1 to 3), Al ₂ O _3, and ITO The selected metal oxide or metal nitride can be used. As the deposition coating method, a sputtering method, a chemical vapor deposition method, an ion plating method, a plasma chemical vapor deposition method or a sol-gel method may be used.

The inorganic hard coating layer including the inorganic particles formed on the gas barrier layer may be prepared by adding inorganic particles to a sol-gel or an organic coating solution, and the inorganic particles serve as a seed and have a crosslinking degree. By increasing the cross-linked structure to increase the hardness and dimensional stability of the substrate surface it can be imparted chemical and scratch resistance.

As the organic coating solution, it is preferable to use an acrylic or epoxy polymer.

The inorganic particles are preferably in the form of plates or spheres, and in the case of spheres, the diameter of the particles is preferably from 100 to 1000 nm, and in the case of the plates, the height is preferably from 1 to 10 nm. Specific examples of the inorganic particles include glass flake, nanoclay or silica particles.

The inorganic particles preferably contain 1 to 50 parts by weight based on 100 parts by weight of the sol state buffer composition to which the inorganic particles are added, but may be variously adjusted according to desired physical properties.

In addition, in the present invention, the flatness of the inorganic hard coating layer including the inorganic particles is also very important. Since devices such as ITO used in the LCD process or the OLED process are deposited directly on the inorganic hard coat layer, these devices may have low This phenomenon is concentrated and can not function. Current trends require better flatness in OLEDs, the next generation of displays rather than LCDs. Therefore, in the present invention, the surface flatness of the inorganic hard coating layer including the inorganic particles is preferably about 1 nm, and more preferably 1 nm or less to satisfy such conditions. Specifically, the flatness may have a Ra value of 0.1 to 1.2.

In addition,

a) coating and curing a sol buffer composition on one side of the plastic film to form an organic or organic-inorganic hybrid buffer layer,

 b) coating an inorganic material on the organic or organic-inorganic hybrid buffer layer to form a gas barrier layer,

c) preparing a multilayer film by coating and thermosetting a sol buffer composition to which inorganic particles are added on the gas barrier layer to form an inorganic hard coating layer;

It provides a method of manufacturing a plastic substrate of a multi-layer structure comprising a.

A) is a step of forming an organic or organic-inorganic hybrid buffer layer by coating and curing the sol buffer composition on one side of the plastic film. The organic or organic-inorganic hybrid buffer layer may be prepared by partially hydrolyzing the buffer composition to form a sol solution, and then coating and curing the same on a plastic film. The coating method may be a method such as spin coating, roll coating, bar coating, dip coating, gravure coating or spray coating. The sol curing method may be a thermosetting, UV curing, infrared curing or high frequency heat treatment. The thickness of the organic-inorganic hybrid buffer layer after curing is 0.5 to 20 μm, preferably 2 to 10 μm, more preferably 1 to 5 μm.

B) is a step of forming a gas barrier layer by coating an inorganic material on the organic or organic-inorganic hybrid layer. The gas barrier layer may be prepared by physically or chemically depositing a transparent inorganic material having a high density or a thin metal thin film on a nanometer scale by an organic or organic-inorganic hybrid buffer layer. As the deposition coating method, a sputtering method, a chemical vapor deposition method, an ion plating method, a plasma chemical vapor deposition method or a sol-gel method may be used. The thickness of the gas barrier layer formed through the method is 5 to 1000 nm, preferably 20 to 500 nm, more preferably 50 to 200 nm.

C) is a step of preparing a multi-layer film by coating an sol buffer composition to which the inorganic particles are added on the gas barrier layer and thermosetting to form an inorganic hard coating layer. The inorganic hard coating layer may be prepared by coating a sol solution by spin coating, roll coating, bar coating, dip coating, gravure coating, or spray coating, and curing by thermal curing, UV curing, infrared curing, or high frequency heat treatment. The thickness after curing may be 0.5 to 20 μm, preferably 2 to 10 μm, more preferably 1 to 5 μm.

The buffer composition of the sol state in which the inorganic particles are added preferably has a viscosity of 10 to 50,000 cps to prevent the inorganic particles from being precipitated by gravity. When the viscosity of the buffer composition is less than 10cp, the inorganic particles may be precipitated by gravity during storage or after coating of the solution, causing uneven distribution of inorganic particles. In addition, if the amount exceeds 50000cp, it is difficult to disperse the inorganic particles in the solution and the inorganic particles may protrude on the coating surface, causing coating surface defects.

In addition, the present invention provides a multi-layered plastic substrate having a symmetrical structure around the film by bonding the surfaces of the plastic film is not formed with a multi-layer film of the multi-layered plastic substrate.

The plastic substrate of the multilayer structure forming the symmetrical structure forms a symmetrical structure so that the plastic substrate does not bend in one direction due to temperature change. In addition, the multi-layered plastic substrate constituting the symmetrical structure can increase productivity by using a simple process of laminating each other between the plastic films, and even with low-cost equipment, small linear expansion coefficient, excellent dimensional stability, gas barrier property, and excellent surface hardness. It is possible to manufacture a plastic substrate having a.

Bonding method between the plastic film of the multi-layer film may be made by an acrylic adhesive or a thermal bonding method commonly used as an adhesive, but is not necessarily limited thereto. At this time, the content of the adhesive is not particularly limited, but the thickness of the formed adhesive layer is preferably 0.1 to 10 ㎛.

In addition, the present invention provides a display device or a solar cell including the plastic substrate of the multi-layer structure.

The present invention also provides a packaging material and a container including a plastic substrate of a multi-layer structure.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are merely to illustrate the invention and the scope of the present invention is not limited to the following examples.

Example  One

100 micron-thick PET (Polyethyleneterephthalate, SH38, SKC) film produced by a biaxial stretching extrusion process was coated with a double-sided acrylic primer to heat the film in a 150 ° C convection oven for 1 minute to remove residual stress Used as.

The initiators for forming the organic-inorganic hybrid buffer layer include 32.5 parts by weight of tetraethoxysilane, 64.0 parts by weight of glycidyloxypropyltrimethoxysilane, 0.5 part by weight of aminopropyltrimethoxysilane, and 2.0 parts by weight of aluminum butoxide. 1.0 parts by weight of zirconium propoxide was used, and 80.0 parts by weight of distilled water was added thereto to partially hydrolyze at 25 ° C. for 24 hours to prepare a sol buffer composition. The buffer composition was bar-coated on one side of PET, followed by gel drying for 1 hour in a convection oven at 125 ° C. after drying the solvent at 50 ° C. for 3 minutes. The thickness of the organic-inorganic hybrid buffer layer measured by alpha stepper after gel reaction was 3 microns. Inject 50 sccm of Ar gas using Atec Systems' DC / RF magnetron sputter on the buffered gel layer, and deposit silicon oxide (SiOx, x) for 10 minutes at 1000 Watt of RF (13.56MHz) power under a pressure of 5 mtorr. An integer of = 1-4) and a thin film was deposited. The thickness of the silicon oxide film observed by SEM was 100 nm. Thereafter, 10 parts by weight of plate-shaped glass flakes (Glass Flake Co., Ltd. GF100) having an average thickness of 1 mm and an average size of 1000 mm were added to 100 parts by weight of the buffer composition. After sufficiently kneading to prevent precipitation of the inorganic particles, a buffer composition having a uniform composition was bar coated on the silicon oxide film. Drying of the buffer layer of the first layer and the reaction under the same conditions as the gel reaction to form a second coating layer to prepare a plastic substrate of a multi-layer structure.

Example  2

Except for adding nanoclay (nanoclay) to the inorganic particles of Example 1 was prepared in a multi-layered plastic substrate in the same manner as in Example 1. The nanoclay is composed of several particles, one particle having a height of 10 nm or less, and the secondary particles of the primary particles of about 5 to 20 nm in length and width are aggregated.

Example  3

A plastic substrate having a multilayer structure was prepared in the same manner as in Example 1, except that spherical silica having a diameter of 500 nm was added as an inorganic particle in Example 1.

Comparative example

A plastic substrate having a multi-layered structure was manufactured in the same manner as in Example 1, except that the coating layer formed by the sol-gel reaction without laminating inorganic particles in the hard coat layer was laminated in Example 1.

Experimental Example

The plastic substrate of the multilayer structure prepared in Examples 1 to 3 and Comparative Examples was measured by the following method by measuring the oxygen transmittance, water vapor transmission rate, strain temperature, light transmittance, haze and pencil hardness as the main properties of the substrate for display devices. The results are shown in Table 1 below.

1) Oxygen permeability: measured with a relative humidity of 0% at room temperature by the method of ASTM D 3985 using OX-TRAN 2/20 of MOCON.

2) Water vapor transmission rate: Using a PERMATRAN-W-3 / 33 was measured for 48 hours at room temperature with a relative humidity of 100% by the method of ASTM F 1249.

3) Deformation temperature: The thermal mechanical analyzer (TMA) was used to measure the inflection point of the sudden change in length at 5gf.

4) Light transmittance: Based on ASTM D1003, each of them was measured in the visible light range of 380 to 780 nm using a Varian UV spectrometer.

5) Haze: Hazemeter TC-H3DPK, manufactured by Tokyo Denshoku, was measured by ASTM D1003.

6) Pencil Hardness: Pencil hardness was measured by the method of ASTM D3363 under a load of 200g. Under the load of 200g, various pencils of different hardness were scratched two or more times in sequence, and the pencil traces were visually observed, and the hardness of the pencil without scratching was measured as the pencil hardness of the film surface.

[Table 1]

1 is a cross-sectional view of a plastic substrate of a multilayer structure of the present invention.

Figure 2 is a cross-sectional view of a multi-layer plastic substrate symmetrical by bonding the plastic substrate of the multi-layer structure of the present invention.

Claims (21)

An organic or organic-inorganic hybrid buffer layer, a gas barrier layer and an inorganic hard coating layer in which 1 to 50 parts by weight of inorganic particles are added to 100 parts by weight of a sol state buffer composition are sequentially stacked on a plastic film. The multilayer plastic substrate of claim 1, wherein the plastic film is selected from the group consisting of a single polymer, at least one polymer blend, and a polymer composite material containing an organic or inorganic additive. The multilayer plastic substrate of claim 2, wherein the polymer composite material containing the inorganic additive is a polymer-clay nanocomposite in which clay nanomaterials are dispersed in a polymer matrix. The method according to claim 1, wherein the organic or organic-inorganic hybrid buffer layer, 20 to 99.99% by weight of an organosilane selected from the group consisting of compounds represented by the following formula (1), and a compound represented by the following formula (2) A plastic substrate having a multilayer structure formed from a partial hydrolyzate of a buffer composition comprising 0.01 to 80% by weight of a metal alkoxide selected from at least one of: [Formula 1] (R ¹ ) _m -Si-X _(4-m) Wherein X may be the same or different from each other, and hydrogen, halogen, alkoxy having 1 to 12 carbon atoms, acyloxy, alkylcarbonyl, alkoxycarbonyl, or -N (R ² ) ₂ , wherein R ² is H, or Alkyl having 1 to 12 carbon atoms), R ¹ may be the same or different from each other, alkyl, alkenyl, alkynyl, aryl, arylalkyl, alkylaryl, arylalkenyl, alkenylaryl, arylalkynyl, alkynylaryl, halogen, substituted Amino, amide, aldehyde, keto, alkylcarbonyl, carboxy, mercapto, cyano, hydroxy, alkoxy having 1 to 12 carbon atoms, alkoxycarbonyl having 1 to 12 carbon atoms, sulfonic acid, phosphoric acid, acryloxy, methacrylic Oxy, epoxy or vinyl, Wherein oxygen or —NR ² (wherein R ² is H, or alkyl having 1 to 12 carbon atoms) is inserted between the radicals R ¹ and Si and is — (R ¹ ) _m -O-Si-X _(4-m) or ( R ¹ ) _m- NR ² -Si-X _(4-m) , where m is an integer of 1 to 3. [Formula 2] M- (R ³⁾ _z In the formula, M represents a metal selected from the group consisting of aluminum, zirconium, and titanium, R ³ may be the same or different from each other, halogen, alkyl having 1 to 12 carbon atoms, alkoxy, acyloxy, or hydroxy group And Z is an integer of 3 or 4. The method of claim 1, wherein the gas barrier layer is SiO _x (where x is an integer of 1 to 4), SiO _x N _y (where x and y are each an integer of 1 to 3), Al ₂ O ₃ And ITO formed from at least one inorganic material selected from the group consisting of multi-layered plastic substrates. The method of claim 4, wherein the buffer composition is a metal, glass powder, diamond powder, silicon oxide, clay, calcium phosphate, magnesium phosphate, barium sulfate, aluminum fluoride, calcium silicate, magnesium silicate, barium silicate, barium carbonate, barium hydroxide A plastic substrate having a multi-layer structure, further comprising a filler selected from the group consisting of siloxane, and aluminum silicate. The multi-layered plastic substrate of claim 1, wherein the inorganic hard coating layer is formed of a sol-gel or an organic coating liquid and inorganic particles. The plastic substrate of claim 1, wherein the inorganic particles are plate or spherical glass flakes, nanoclays, or silica particles. delete a) coating and curing a sol buffer composition on one side of the plastic film to form an organic or organic-inorganic hybrid buffer layer, b) coating an inorganic material on the organic or organic-inorganic hybrid buffer layer to form a gas barrier layer, c) coating and thermosetting the sol buffer composition to which 1 to 50 parts by weight of inorganic particles are added to 100 parts by weight of the sol buffer composition on the gas barrier layer to form an inorganic hard coating layer, Method of manufacturing a plastic substrate of a multi-layer structure comprising a. The method of claim 10, wherein the a) organic or organic-inorganic hybrid buffer layer has a thickness of 0.5 to 20 μm. The method of claim 10, wherein the gas barrier layer has a thickness of 5 to 1000 nm. The method of claim 10, wherein the c) inorganic hard coating layer has a thickness of 0.5 to 20 ㎛. The method of claim 10, wherein the sol state buffer composition to which the inorganic particles are added has a viscosity of 10 to 50,000 cps. The plastic substrate having the multilayer structure of any one of claims 1 to 8 or the plastic substrate having the multilayer structure manufactured by the method of any one of claims 10 to 14 is bonded to each other by the surfaces of the plastic film on which the multilayer film is not formed. Plastic substrate with a multi-layered structure forming a symmetrical structure. The method of claim 15, wherein the bonding method of the plastic substrate of the multi-layered structure forming the symmetrical structure is a plastic substrate of a multi-layered structure of a symmetric structure that is made by an acrylic adhesive or a thermal bonding method. The method according to claim 15, wherein the thickness of the adhesive layer of the plastic substrate of the multi-layered structure to form the symmetrical structure is a plastic substrate of a multi-layered structure consisting of a symmetrical structure of 0.1 to 10 ㎛. A display device comprising the plastic substrate of any one of claims 1 to 8. A solar cell comprising the plastic substrate of any one of claims 1 to 8. The packaging material containing the plastic substrate of any one of Claims 1-8. A container comprising the plastic substrate of any one of claims 1 to 8.

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