KR20090125697A - Filter for shielding electromagnetic interference and preparing method thereof, and display device comprising the same - Google Patents

Abstract

PURPOSE: An electromagnetic shielding filter, a manufacturing method thereof, and a display device are provided to print paste composition on the tin surface of a transparent reinforcing glass substrate, thereby minimizing the reduction of external light reflection and wet proof property. CONSTITUTION: A tin surface having relatively much tin distribution quantity is included in one surface of a transparent reinforcing glass substrate(20). An air surface having relatively smaller tin distribution quantity than the tin surface is included in the other surface of the transparent reinforcing glass substrate. An electromagnetic shielding member(10) is formed in a mesh shape on the tin surface of the transparent reinforcing glass substrate. The electromagnetic shielding member is connected to a ground member(40) to be grounded. The transparent reinforcing glass substrate is manufactured by reinforcing a plate glass which is manufactured in a float method. In the lower part of the air side of the transparent reinforcing glass substrate, a near infrared blocking layer(50) and an anti-reflective layer(60) are included.

Description

FILTER FOR SHIELDING ELECTROMAGNETIC INTERFERENCE AND PREPARING METHOD THEREOF, AND DISPLAY DEVICE COMPRISING THE SAME}

The present invention is applied as an electromagnetic shielding filter of a display device such as a plasma display panel, to improve the quality of the pattern, the printability and the continuous process, and in particular, the optical properties of the plasma display are excellent and the printing surface is exposed to the outside air. The present invention relates to an electromagnetic wave shielding filter, a method for manufacturing the same, and a display device having the same, which may have moisture resistance.

Recently, various kinds of display devices have been developed. For example, a plasma display device (PDP), a liquid crystal display device (LCD), an organic light emission display device (OLED), and the like are being developed. Such display devices are used for many products that require image display because they are thin and light in weight.

Meanwhile, electromagnetic interference (EMI) is emitted from a plurality of electronic elements included in the display device. EMI can cause the display device to malfunction or harm the human body. Therefore, an electromagnetic shielding filter is attached to the display device to shield the EMI.

The electromagnetic shielding filter, in addition to the electromagnetic shielding, to correct the color, to reduce the external light reflection, to prevent the malfunction of the remote control by blocking the near-infrared, to protect the module from external shock, and to prevent the glass from scattering when the front glass breaks.

Conventional electromagnetic shielding filter manufacturing method, as shown in Figure 1a, in general, by forming an EMI mesh pattern through a lamination process, an exposure and development process, an etching process and a strip process in a conventional manner using a Cu substrate. ought. The EMI filter formed by the above method includes a Cu mesh pattern on a substrate on which a pressure-sensitive adhesive layer and a PET film are formed on a glass substrate, and also a near infrared layer (NIR), a color correction layer, and an anti-reflection layer (Anti-reflection) AR) is provided to form a double-sided stack of the functional layers and the Cu mesh typically based on the base substrate. The Cu mesh pattern formed by the above method may have a form as illustrated in FIG. 1B. At this time, unlike the drawing, the optical functional layer may be changed in position as necessary. For example, the NIR, color correction layer, and AR layer may be formed on both sides of the PET film on a substrate including the PET film. However, the existing film mesh type such as Cu mesh is laminated on both sides when manufacturing the filter, and the transparent process must be further performed in order to satisfy the optical characteristics, so that the process is complicated.

In addition, after the conductive paste is printed and fired on the air surface (air surface) of the glass substrate in the manufacturing method of the electromagnetic wave shielding filter using the offset process, the antireflection layer, color correction, near infrared layer, etc. are formed on the opposite side of the printing layer and then made transparent. When the process is performed, the entire printed layer (air surface) of the filter may be exposed to the outside air in the final product. In this case, there is a problem that the glass substrate becomes cloudy due to cloudiness due to weak moisture resistance, thereby degrading the quality and optical properties of the product. Therefore, the method has to stack both sides of the functional film to protect the printing surface, the double-sided lamination causes a problem that the process is complicated.

Therefore, the present invention forms an electromagnetic shielding layer directly on the tin surface (tin surface) of the transparent tempered glass substrate by applying an offset process, and by forming a functional film in a cross-sectional layer on the air surface (air surface) opposite the display It is an object of the present invention to provide an electromagnetic wave shielding filter and a method for manufacturing the same, which may have excellent optical characteristics and have moisture resistance.

The present invention also provides a display device including the electromagnetic wave shielding filter.

The present invention

A transparent tempered glass substrate having an air surface having a relatively small tin distribution on one side, and an air surface having a relatively small tin distribution on the other side, and

It provides an electromagnetic shielding filter including an electromagnetic shielding member formed in a mesh form on the tin surface of the transparent tempered glass substrate.

The transparent tempered glass substrate is produced by reinforcing the plate glass manufactured by the float (float) method in the present invention is to be printed by dividing the tin surface (tin surface) and the air surface (Air surface).

A color correction and near-infrared blocking layer sequentially formed on an air surface opposite to the printing of the transparent tempered glass substrate; And an antireflection layer. That is, the color correction and near-infrared blocking layer may be used on a glass substrate including a film such as PET at the bottom, formed on both sides of the film, or laminated on each side of the film.

The color correction and near-infrared layer may contain a near-infrared shielding pigment having a near infrared absorption function of 850-1250 nm wavelength and a selective light absorbing material for neon wavelength blocking and color correction. The near-infrared shielding pigment may include at least one material selected from the group consisting of nickel complex, phthalocyanine, cyanine, dimonium, and mixtures thereof. The selective light absorbing material for blocking the neon wavelength and color correction may include at least one material selected from the group consisting of azo, stryl, cyanine, anthraquinone and tetraazapopyrine. The near-infrared layer and the color correction layer may be prepared by mixing the above-mentioned near-infrared absorbing material and the selective light-absorbing material with a polymer resin and a solvent, and coating a transparent substrate such as a glass substrate including a film.

The anti-reflection layer may include a low refractive index layer including a low refractive index material and a high refractive index layer including a high refractive index material. The low refractive index material may include at least one material selected from the group consisting of fluorine-based, silicon oxide, magnesium fluoride, aluminum oxide and the like. The high refractive index material may include at least one material selected from the group consisting of inorganic fine particles such as titanium dioxide, indium tin oxide, zinc oxide, antimony, tin oxide, cerium oxide, zirconium oxide, and antimony oxide. The anti-reflection layer may be formed by alternately coating a coating liquid containing a high refractive index material and a coating liquid containing a low refractive index on the hard coating layer by forming a hard coating layer on the substrate.

The electromagnetic shielding member is preferably formed by printing a black conductive paste composition on the substrate and firing the same. In this case, the black conductive paste composition is an electromagnetic wave shielding filter paste composition applied to a display device such as a plasma display panel, and preferably, the black conductive paste composition is printed (for example, offset printed) on a glass substrate and fired. An electromagnetic wave shielding filter for the display device can be provided.

The black conductive paste composition is 5 to 15 parts by weight of acrylate polymer resin and monomer or oligomer, 5 to 15 parts by weight of solvent, 1 to 10 parts by weight of glass powder, 50 to 90 parts by weight of conductive metal and 1 to 10 parts by weight of black pigment. It may include. Moreover, it is preferable that such paste composition of this invention contains 0.05-1 weight part of dispersing agents further.

In addition, the present invention

Providing a grooved gravure roll in the form of a mesh,

Filling the groove with a black conductive paste composition;

Providing a blanket roll facing the gravure roll and rotating in a direction opposite to the direction of rotation of the gravure roll,

Transferring the conductive paste composition to the blanket roll while rotating the gravure roll,

Providing a transparent tempered glass substrate having a tin surface on one side, the tin surface having a relatively large amount of tin distributed, and having an air surface having a relatively small amount of tin distributed on the other side,

Applying the conductive paste composition onto the tin surface of the transparent tempered glass substrate while the blanket roll moves over the transparent tempered glass substrate, and

Firing the conductive paste composition to form a shielding member consisting of a single layer for shielding electromagnetic waves on the tin surface of the transparent tempered glass substrate.

In the providing of the gravure roll, the groove preferably includes at least one first groove portion extending in one direction, and at least one second groove portion crossing the first groove portion. Preferably, the one or more first grooves include a plurality of first grooves, and the average pitch of the plurality of first grooves is greater than zero and less than or equal to 500 μm. An average pitch of the plurality of first grooves may be 200 μm to 400 μm. The groove extends in an oblique direction, and an angle formed between the tangential line formed by the gravure roll and the blanket roll and the first groove portion may be 20 ° to 70 °.

The present invention also includes a transparent tempered glass substrate, an electromagnetic shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate, and a display panel which displays an image and faces the transparent tempered glass substrate. ,

The electromagnetic shielding member is applied to shield electromagnetic waves emitted from the display panel, and the black conductive paste composition is formed by offset printing and baking the tin surface of a transparent tempered glass substrate, thereby providing a display device.

Hereinafter, the present invention will be described in detail.

The present invention relates to an electromagnetic wave shielding filter and a display device using the same, which are excellent in appearance quality of a pattern and can improve a continuous process, and are particularly excellent in printability and optical characteristics.

First, in the present invention, the "transparent tempered glass substrate" uses a transparent tempered glass substrate in which a plate glass made by a float method is strengthened by a conventional method. In addition, the surface which is in contact with the molten metal (tin) in the plate glass manufacturing process is called a tin surface (tin surface), the opposite surface is characterized in that the printing / firing by dividing the air surface (air surface).

In this case, in the present invention, the tin surface (tin surface) means a surface in which a predetermined amount of tin is distributed on the transparent tempered glass substrate and refers to a surface having a relatively large tin distribution, and the air surface is in contact with air on the opposite side of the tin surface. It means that the tin distribution is relatively small compared to the tin surface.

In other words, in the glass-toughened transparent tempered glass manufactured by the above-described plot method, the tin surface is defined as a tinier surface in which the irradiated light is diffused when the light source is illuminated by using a tin detector under dark conditions. In addition, a relatively transparent layer is divided into air planes and used in an offset process.

As a result of the experiments of the present inventors, in the offset printing process using the black conductive paste composition, when the paste composition is printed on the tin surface of the transparent tempered glass substrate, it has been found that a product having a filter structure in which the printing surface is exposed is possible. That is, in the above method, unlike the conventional film products such as Cu mesh, when filtering, the electromagnetic wave shielding mesh is formed directly on the glass substrate, and thus the optical transparency is excellent, and the electromagnetic shielding mesh is formed on the tin surface and the antireflection layer (AR ) And near infrared ray shielding (NIR) and color correction layer formed on the opposite side of the printing surface can also have moisture resistance, which can simplify the structure and process of the filter. In addition, the yellowing phenomenon is generated by the reaction of the conductive metal and tin surface included in the electromagnetic shielding member, which is a printed layer, the present invention surprisingly found that the yellowing phenomenon shows an improvement in external light reflection and blackness. In other words, in the past, yellowing was a problem, but by using the yellowing phenomenon, which is relatively larger than the air plane, the present invention can improve external light reflection and blackness compared to the air plane, and thus it is confirmed that it is advantageous in optical properties. will be. Therefore, the electromagnetic wave shielding filter of the present invention allows the printed layer to face the panel portion when applied to the panel, and the glass layer and the optical function layer may have a structure exposed to the outside.

Therefore, the electromagnetic shielding filter formed by printing and baking on a specific tempered glass substrate using the black conductive paste composition of the present invention includes a mesh pattern having a constant shape, thickness and line width, and in particular, can simplify the process, and By remarkably improving the optical characteristics, it is possible to improve the continuous process together with the quality improvement.

The electromagnetic wave shielding filter of the present invention includes: i) a transparent tempered glass substrate having a tin surface having a relatively large tin distribution on one side, and an air surface having a relatively small tin distribution on the other side, And ii) an electromagnetic shielding member formed in a mesh form on the tin surface of the transparent tempered glass substrate. The electromagnetic shielding member is applied to shield electromagnetic waves.

A color correction layer and a near-infrared blocking layer that are sequentially formed in the lower portion of the air surface of the transparent tempered glass substrate; And an antireflection layer. Therefore, the antireflection layer is exposed to the outside air.

In addition, the color correction and near-infrared blocking layer and the anti-reflection layer may be formed on both sides of the film in a form including a film such as PET under the air surface of the transparent tempered glass substrate. In this case, the anti-reflection layer is preferably located at the bottom of the glass substrate. For example, the structure may include a near infrared ray shielding layer, a PET film, and a color correction layer at a lower portion of the air surface of the transparent tempered glass substrate, and an antireflection layer may be disposed under the lower portion of the air surface. The film having the structure may be laminated using a pressure-sensitive adhesive or the like in the lower portion of the air surface of the transparent tempered glass substrate. In another example, the method of the present invention may sequentially form a near infrared ray shielding layer, a PET film, a color correction layer and an antireflection layer by using a method such as coating on the lower portion of the glass substrate.

In addition, the color correction and near-infrared blocking layer and the anti-reflection layer, in the form of a film such as PET in the lower portion of the air surface of the transparent tempered glass substrate, each formed on one side of the film, after Two formed films are laminated and used. In this case, the anti-reflection layer is preferably located at the bottom of the glass substrate. As an example having such a structure, a color correction layer is formed on the upper part of the PET film, a near infrared ray blocking layer is formed on the upper part of the PET film, and then the two films are laminated and used. Therefore, the structure includes a PET film, a color correction layer, a PET film, and a near infrared ray shielding layer at a lower portion of the air surface of the transparent tempered glass substrate, and an anti-reflection layer may be positioned under the structure. Alternatively, the stacking order of the two layers may be reversed, and the lower surface of the transparent tempered glass substrate may include a PET film, a near-infrared shielding layer, a PET film, and a color correction layer, and an anti-reflection layer may be disposed under the air layer. Here, in the two films, the other surface of the PET film may include all of the glass substrate, or only one of them may include the glass substrate. The film having the structure may be laminated using a pressure-sensitive adhesive or the like in the lower portion of the air surface of the transparent tempered glass substrate. As another example, the method of the present invention, by using a method such as coating on the lower portion of the glass substrate can be formed sequentially in each layer.

The color correction and near-infrared layer may contain a near-infrared shielding pigment having a near infrared absorption function of 850 to 1250 nm wavelength and a selective light absorbing material for neon wavelength blocking and color correction. Examples of the near-infrared shielding pigment may include a material selected from the group consisting of nickel complex, phthalocyanine, cyanine, dimonium compounds, and mixtures thereof. In addition, the selective light absorbing material for the neon wavelength blocking and color correction may include at least one material selected from the group consisting of azo, stryl, cyanine, anthraquinone and tetraazapopyrine compounds. The near-infrared layer and the color correction layer may be prepared by mixing the above-described near-infrared absorbing material and the selective light-absorbing material with a polymer resin and a solvent, and coating the lower substrate with a transparent substrate such as a glass substrate including a film.

The anti-reflection layer may include a low refractive index layer including a low refractive index material and a high refractive index layer including a high refractive index material. The low refractive index single layer is easy to manufacture, but the antireflection performance may be lowered than that of the multilayer stack. The low refractive index material may include at least one material selected from the group consisting of fluorine-based, silicon oxide, magnesium fluoride, aluminum oxide and the like. The high refractive index material may include, for example, at least one material selected from the group consisting of inorganic fine particles such as titanium dioxide, indium tin oxide, zinc oxide, antimony, tin oxide, cerium oxide, zirconium oxide, and antimony oxide. . The anti-reflection layer may be formed by alternately coating a coating liquid containing a high refractive index material and a coating liquid containing a low refractive index on the hard coating layer by forming a hard coating layer on the substrate.

The electromagnetic shielding member may be formed by printing and baking a black conductive paste composition on a tin surface of a transparent tempered glass substrate, and preferably, the paste composition is formed by offset printing (particularly, gravure offset printing) and firing the paste composition. Can be.

The black conductive paste composition includes an acrylate polymer resin and a monomer or oligomer, a solvent, a dispersant, a glass powder, a conductive metal, and a black pigment.

In the black conductive paste composition, as the acrylate polymer resin, methyl acrylate (MA), butyl methacrylate (BM), hydroxyethyl methacrylate (HEMA), methyl methacryl Any one or two polymers selected from the group consisting of methylmethacrylate (MMA), ethyl acrylate (EA), ethylhexyl acrylate, nonyl acrylate, and methacrylates thereof; The above copolymer can be used. Preferably, as the acrylate polymer resin, methyl acrylate (MA), BM (butyl methacrylate, butyl methacrylate), HEMA (hydroxyethyl methacrylate, hydroxyl methacrylate), and MMA (methlmethacrylate, methyl Methacrylate) copolymerized in a weight ratio of 10 to 30:30 to 60:10 to 20:10 to 20 can be used. However, the acrylate polymer resin is not limited thereto, and any acrylate polymer resin known to be usable as a binder resin in other conductive paste compositions for electromagnetic wave shielding filters may be used without particular limitation.

The acrylate polymer resin uniformly disperses other components of the black conductive paste composition, that is, glass powder, conductive metal, black pigment, and the like, and the electromagnetic wave shielding filter formed from the black conductive paste composition provides uniform electromagnetic shielding performance and optical performance. It plays a role in showing characteristics.

Preferably, the acrylate polymer resin has a weight average molecular weight of 5,000 to 100,000, more preferably 5,000 to 60,000. When the weight average molecular weight of the acrylate polymer resin is less than 5,000, the glass transition temperature of the polymer is low, and thus the flow characteristic of the polymer is increased. Therefore, the black conductive paste composition may have a gravure groove during a printing process (for example, a gravure offset printing process). Pattern transfer to the blanket is difficult, and exceeding 100,000 makes it difficult to add the composition into the gravure groove due to the excessive elastic properties of the polymer.

The monomer or oligomer preferably comprises at least one member selected from the group consisting of an acrylate compound, an alkoxylate compound, dimethyl sulfoxide and an unsaturated polyester compound.

Examples of the monomer or oligomer include methyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, glycidyl methacrylate, butyl methacrylate, ethyl methacrylate, benzyl methacrylate and ethyltriglycol. Methacrylate, nonyl acrylate, nonyl methacrylate, ethyl acrylate, ethyl methacrylate, ethylhexyl acrylate, ethylhexyl methacrylate, urethane acrylate, lauryl acrylate, oligoether acrylate , Polyether acrylate compound, polyester acrylate compound, silicone acrylate, trimethylolpropane triacrylate, neopentyl glycol hydroxypivalate modified caprolactone (Neopentylglycol hydroxypivalate diacrylate modified caprolactone), polyethylene glycol dia Relate, polypropylene glycol diacrylate, tetraethylene glycol diacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate modified ethylene oxide (modified EO), trimethylolpropane triacrylate modified Polypropylene oxide (modified PO), dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate modified caprolactone, ditrimethylolpropane Tetraacrylate, pentaerythritol tetraacrylate, pentaerythritol ethoxylated triacrylate, urethane methacrylate, lauryl methacrylate, oligoether methacrylate, polyether methacrylate System Water, polyester methacrylate type compound, silicone methacrylate, trimethylol propane trimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, pentaerythritol Trimethacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol pentamethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol tetramethacrylate, pentaerythritol ethoxylated Trimethacrylate, Ethylene Glycol Dimethacrylate, Diethylene Glycol Dimethacrylate, Bisphenol A Ethoxylated Dimethacrylate, Trimethylolpropane Ethoxylate (4/15 EO / OH) Trimethylolpropane ethoxylate (20/3 EO / OH), trimethylolpropane propoxylate (1 PO / OH), dimethyl sulfoxide and unsaturated polyesters. At this time, the dimethyl sulfoxide is generally used as a solvent, in the case of the present invention can be used as a monomer replacement. More preferably, the monomer or oligomer is at least one selected from the group consisting of urethane acrylate, trimethylolpropane triacrylate modified ethylene oxide, trimethylolpropane triacrylate modified propylene oxide and bisphenol A ethoxylated dimethacrylate. Can be.

In addition, the monomer or oligomer is not particularly limited to the above examples, it is possible to prevent the drying in the offset method, to improve the transferability of the paste, and to use any monomer or oligomer usable in the conductive paste composition for electromagnetic wave shielding filter. It may be.

The content of such monomers or oligomers is preferably included in an amount of 10 to 90 parts by weight, based on 100 of the total amount of the acrylate polymer resin and the monomer or oligomer. Therefore, the weight ratio of the acrylate polymer resin and the monomer or oligomer may be 10:90 to 90:10. In this case, when the content of the monomer or oligomer is less than 10 parts by weight, there is a problem that the drying prevention effect of the paste composition is reduced by reducing the drying effect, and when the content of the monomer or oligomer exceeds 90 parts by weight, the elasticity of the paste composition is reduced and the pattern spreading phenomenon is deepened or printed. It may deteriorate and may not have a shape.

The content of the acrylate polymer resin and the monomer or oligomer is preferably included in the total paste composition, 5 to 15 parts by weight. When the content of the acrylate polymer resin and the monomer or oligomer is less than 5 parts by weight, there is a possibility that a problem occurs in the printing process due to the decrease in elasticity of the paste composition. When the content of the acrylate polymer resin exceeds 15 parts by weight, the electrical resistance of the pattern formed from the paste composition is increased. Increasing problems may arise.

On the other hand, in the black conductive paste composition, the solvent is a medium for dissolving other components, it is preferably included in 5 to 15 parts by weight in the total paste composition. When the content of the solvent is less than 5 parts by weight, there is a problem that the drying speed of the paste composition becomes difficult to proceed with continuous printing, and when the content of the solvent exceeds 15 parts by weight, the viscosity of the paste composition is lowered and the printability is deteriorated.

As such a solvent, any solvent known to be usable in the conductive paste composition for an electromagnetic shielding filter can be used without particular limitation, but preferably at least one or more of a high boiling point solvent having a boiling point of 200 ° C or higher and a boiling point of less than 200 ° C It may contain at least one or more of low boiling point solvents.

By including the high boiling point solvent and the low boiling point solvent together, the viscosity and fluidity of the paste composition can be maintained at a desirable level, and thus, the process of printing the paste composition on a glass substrate transfers the pattern of the paste composition to a pattern. In addition to being easy, the spreading of the pattern is suppressed, so that the straightness of the pattern can be further improved.

As the high boiling point solvent, for example, one or more solvents selected from the group consisting of gamma butyrolactone, butyl carbitol acetate, carbitol, methoxymethyl ether propionate and tepinol can be used. Any organic solvent known to be usable for the conductive paste composition for electromagnetic wave shielding filter having the above boiling point can be used.

Moreover, as said low boiling point solvent, propylene glycol monomethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether propionate, ethyl ether, for example. One or more solvents selected from the group consisting of propionate, propylene glycol monomethyl ether acetate, methyl ethyl ketone, and ethyl lactate can be used, and used in conductive paste compositions for electromagnetic wave shielding filters while having a boiling point of less than 200 ° C. Any organic solvent known to be possible can be used.

In addition, the solvent may include 12 to 88% by weight of the high boiling point solvent and 12 to 88% by weight of the low boiling point solvent. If the high boiling point solvent is included in the solvent in an amount less than 12% by weight, and the content of the low boiling point solvent is excessively increased, the rate of fluidity decrease of the paste composition may be too high, so that the transition to the pattern may not be easy. On the contrary, if the content of the high boiling point solvent is excessively increased beyond 88% by weight, as the fluidity of the paste composition is difficult to suppress, the spreading of the pattern is intensified, and thus the straightness of the pattern formed through printing of the paste composition may be reduced. .

Meanwhile, in the black conductive paste composition of the present invention, the glass powder may be Pb-based and Pb-free-based powders, but in terms of environmental regulation, Pb-free-based powders may be used rather than Pb-based powders. It is desirable to consider the removal temperature of the organic material and the improvement of pattern adhesion to the glass substrate. Such Pb-free powders include Bi-based glass powders such as Bi ₂ O ₃ -based glass powders. In addition, colored glass powders prepared by incorporating black or colored pigments in the production of glass powders or glass powders containing colored components such as V ₂ O ₅ can also be preferably used.

The content of the glass powder may be 1 to 10 parts by weight, preferably 2 to 7 parts by weight, in the total paste composition. If the content of the glass powder is less than 1 part by weight, there is a problem in that the adhesion of the paste composition to the glass substrate is weakened. If the content of the glass powder is more than 10 parts by weight, the electrical resistance of the pattern formed from the paste composition is increased, thereby deteriorating the electromagnetic wave shielding efficiency. .

In addition, in the black conductive paste composition, an electrode metal powder may be used as the conductive metal. More specifically, silver, copper, nickel, tin, or an alloy thereof may be used alone or in combination of one or more thereof.

The content of the conductive metal is preferably 50 parts by weight to 90 parts by weight in the total paste composition. When the content of the conductive metal exceeds 90 parts by weight, the viscosity of the paste composition is increased and the dispersion is difficult, so that the printing characteristics are decreased. When the content of the conductive metal is less than 50 parts by weight, the electromagnetic shielding filter for a display device is due to an increase in the electrical resistance of the pattern formed from the paste composition. The electromagnetic shielding performance required for the performance may be reduced.

In addition, the metal powder used as the conductive metal may preferably have an average particle size of 0.3 ~ 30㎛, more preferably an average particle size of 0.5 ~ 10㎛, most preferably an average of 0.5 ~ 5㎛ May have a particle size. If the metal powder has an average particle size of less than 0.3 μm, dispersion is difficult and the paste composition may have high viscosity or gelation, resulting in poor printing characteristics and good pattern through printing of the paste composition. Difficult to form In addition, when the metal powder has an average particle size that is too large exceeding 30 μm, the metal powder is not uniformly filled in the pattern formed by printing the paste composition, which causes the electromagnetic wave shielding filter to have a uniform electromagnetic shielding. It is difficult to show the performance, and holes and the like are generated in the pattern, so that it is difficult to form a desirable pattern and an electromagnetic shielding filter. Alternatively, if the metal powder has an average particle size of 0.3 to 30 μm, more preferably an average particle size of 0.5 to 10 μm, most preferably an average particle size of 0.5 to 5 μm, Printing characteristics and electromagnetic shielding performance can be further improved, and generation of holes in the pattern can be prevented.

In the black conductive paste composition, the black pigment is used to reduce external light reflection and improve contrast of the display device, and may include cobalt, copper, rudennium, manganese, nickel, chromium, or iron-based compounds. And preferably include cobalt-based compounds. In addition, the black pigment is more preferably used in the form of an auxiliary pigment, such as copper, rudenium, manganese, nickel, chromium or iron, in addition to the cobalt-based compound to improve the blackness.

The black pigment may be included in an amount of 1 to 10 parts by weight, preferably 2 to 7 parts by weight, in the entire paste composition. When the content of the black pigment is less than 1 part by weight, sufficient contrast improvement cannot be expected, and when it exceeds 10 parts by weight, the electrical resistance is increased and the electromagnetic wave shielding property may be deteriorated.

In addition, the black conductive paste composition may further include a dispersant as necessary. The dispersant may be any polymer that is well known or commercially available in the art without particular limitation. The content of the dispersant is preferably contained in 0.05 parts by weight to 1.0 parts by weight in the total paste composition. If the content of the dispersant is less than 0.05 parts by weight, sufficient dispersibility and contrast improvement cannot be expected. If the content of the dispersant is more than 1.0 part by weight, the electrical resistance may be increased to deteriorate electromagnetic wave shielding properties.

In addition, the electromagnetic shielding member may include: i) at least one first shielding portion extending in one direction, and ii) at least one second shielding portion crossing the first shielding portion. In this case, the width of the first shielding portion may be greater than 0 and 50 μm or less, preferably 15 μm to 30 μm. The one or more first shields may include a plurality of first shields, and the average pitch of the plurality of first shields may be greater than 0 and less than or equal to 500 μm. Preferably, the average pitch of the plurality of first shielding parts may be 200 μm to 400 μm.

In addition, the angle formed by the crossing of the first shielding portion and the second shielding portion may be 60 ° to 120 °, and preferably 80 ° to 100 °. Most preferably, the angle formed by the crossing of the first shielding portion and the second shielding portion may be substantially 90 °.

The angle formed by one side of the first shielding portion and the glass substrate may be 20 ° to 70 °, and preferably 35 ° to 55 °.

In addition, the electromagnetic shielding member may have an opening having a polygonal shape, and the opening may be chamfered. The lengths of all sides forming the polygon may be substantially the same, and furthermore, the polygon may be substantially square.

The electromagnetic shielding member may include a conductive metal. The conductive metal may be one or more metals selected from the group comprising silver, copper, tin and nickel.

In addition, the above-described electromagnetic shielding filter may further include an edge layer formed along the edge of the transparent tempered glass substrate. An electromagnetic shielding member may be formed on the edge layer. In this case, the electromagnetic shielding filter may further include a grounding member connected to an end of the electromagnetic shielding member to ground the electromagnetic shielding member.

On the other hand, the present invention provides a display device formed using the paste composition described above.

The display device includes i) the transparent tempered glass substrate, ii) an electromagnetic shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate, and iii) a display panel that displays an image and faces the glass substrate. . In this case, the electromagnetic shielding member is applied to shield electromagnetic waves emitted from the display panel, and is formed by offset printing and baking the black conductive paste composition on the tin surface of the transparent tempered glass substrate.

In the display device, the display panel may include i) a first substrate and a second substrate facing each other, and ii) a black layer disposed between the first substrate and the second substrate. In this case, the electromagnetic shielding member may cross three-dimensionally with the black layer. In addition, the electromagnetic shielding member may contact the second substrate. The thickness of the transparent tempered glass substrate on which the electromagnetic wave shielding member is formed may be equal to or greater than the thickness of the first substrate. In addition, the electromagnetic shielding member may have an opening having a polygonal shape, and the opening may be chamfered. The lengths of all sides forming the polygon may be substantially the same, and furthermore, the polygon may be substantially square.

The electromagnetic shielding member may be formed by offset printing (particularly, gravure offset printing) and baking the paste composition on the tin surface of the transparent tempered glass substrate. In addition, the electromagnetic shielding member may include: i) at least one first shielding portion extending in one direction, and ii) at least one second shielding portion crossing the first shielding portion. In this case, the width of the first shielding portion may be greater than 0 and 50 μm or less, preferably 15 μm to 30 μm. The one or more first shields may include a plurality of first shields, and the average pitch of the plurality of first shields may be greater than 0 and less than or equal to 500 μm. Preferably, the average pitch of the plurality of first shielding parts may be 200 μm to 400 μm.

The angle formed by the crossing of the first shielding portion and the second shielding portion may be 60 ° to 120 °, and preferably 80 ° to 100 °. Most preferably, the angle formed by the crossing of the first shielding portion and the second shielding portion may be substantially 90 °.

In addition, an angle formed by one side of the first shielding portion and the transparent tempered glass substrate may be 20 ° to 70 °, and preferably 35 ° to 55 °.

The display panel may be a plasma display panel.

Hereinafter, the electromagnetic wave shielding filter and the display device will be described with reference to the accompanying drawings so that a person skilled in the art can easily implement the present invention. As can be easily understood by those skilled in the art, the following embodiments are only intended to illustrate the present invention, and various forms without departing from the spirit and scope of the present invention. It can be modified. Where possible the same or similar parts are represented with the same reference numerals in the drawings.

All terms including technical terms and scientific terms used below have the same meaning as those commonly understood by those skilled in the art. Terms defined in advance are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

It is to be understood that the terms first, second and third are used to describe various parts, components, regions, layers and / or sections, but are not limited to these. These terms are only used to distinguish one part, component, region or section from another part, component, region or section. Accordingly, the first portion, component, region, layer or section described below may be referred to as the second portion, component, region, layer or section without departing from the scope of the invention.

2 schematically shows a filter 100 for shielding electromagnetic waves according to an embodiment of the present invention. The enlarged source of FIG. 2 enlarges and shows the inside of the electromagnetic wave shielding filter 100. FIG.

As shown in FIG. 2, the anti-reflective layer 60, which is an optical function layer, is disposed at the top of the filter 100 for electromagnetic wave shielding, and the color correction and near-infrared blocking layer 50 is air of the transparent tempered glass substrate 20. It is arrange | positioned at the surface (Air surface), and it has a structure which an optical function layer is exposed to outside air. In addition, although not shown in the drawings, a tin surface (tin surface) is included in the upper portion of the transparent tempered glass substrate 20 having the color correction and near-infrared blocking layer and the anti-reflection layer at the bottom. In addition, the electromagnetic wave shield member 10, the edge layer 30, and the ground member 40 are disposed on the tin surface toward the panel portion. The present invention uses the above-mentioned transparent tempered glass substrate 20 to form the electromagnetic shielding member 10 by an offset printing method (particularly, gravure offset printing). The long side of the transparent tempered glass substrate 20 is parallel to the x axis, and the short side is parallel to the y axis.

The electromagnetic shielding member 10 is connected to the ground member 40 and grounded. Therefore, the electromagnetic shielding member 10 may absorb and remove electromagnetic waves. As a result, the electromagnetic wave shielding member 10 functions as a filter for shielding electromagnetic waves. The edge layer 30 is formed along the edge of the transparent tempered glass substrate 20, and the ground member 40 is positioned at both ends of the transparent tempered glass substrate 20 in the x-axis direction to ground the electromagnetic shielding member 10. do. In addition, the optical functional layers of the color correction and near-infrared blocking layer 50 and the anti-reflective layer 60 are sequentially formed on the opposite side of the transparent tempered glass substrate on which the electromagnetic shielding member 10 is formed.

As shown in the enlarged circle of FIG. 2, the electromagnetic shielding member 10 is formed in a mesh form. The electromagnetic wave shielding filter 100 is mainly used for a display device. Therefore, the electromagnetic shielding member 10 is formed in a mesh form so that an image emitted from the display device is displayed to the outside. Since the electromagnetic wave shielding member 10 has an opening 109, the electromagnetic wave can be blocked while passing an image through the opening 109.

The electromagnetic shielding member 10 includes a first shielding portion 101 and a second shielding portion 103. The first shielding portion 101 extends in the x-axis direction and intersects with the second shielding portion 103. That is, as shown in the enlarged circle of FIG. 1, the first shielding portion 101 and the second shielding portion 103 meet with each other to form an angle α1. The angle α1 may be 60 ° to 120 °. If the angle α1 is too large or too small, the distance between the first shielding portion 101 and the second shielding portion 103 becomes too close and the aperture ratio may be too small. More preferably, the angle α1 may be between 80 ° and 100 °. In this case, the distance between the first shielding portion 101 and the second shielding portion 103 can be properly maintained. Moreover, it is most preferable if angle (alpha) 1 is substantially 90 degrees.

A method of manufacturing an electromagnetic shielding filter includes i) providing a gravure roll with a groove formed in a mesh shape, ii) filling a black conductive paste composition in the groove, and iii) opposing the gravure roll. Providing a blanket roll that rotates in a direction opposite to the rotational direction of the gravure roll, iv) transferring the conductive paste composition to the blanket roll while rotating the gravure roll, v) a transparent tempered glass substrate (Vi) applying the conductive paste composition onto a tin surface of the transparent tempered glass substrate while the blanket roll moves over the transparent tempered glass substrate, and vii) firing the conductive paste composition to strengthen the transparent Forming a shielding member consisting of a single layer for shielding electromagnetic waves on the tin surface of the glass substrate It may include a system.

At this time, the substrate is cleaned with water through a conventional cleaning device before printing.

The transparent tempered glass substrate is produced by reinforcing the plate glass manufactured by the plot method as described above, in the present invention is divided into a tin surface (tin) surface and the air surface (Air surface) and printed.

In the embodiment of the present invention, in order to form the electromagnetic wave shielding member 10 in the form of a mesh, a gravure roll 55 (shown in FIG. 4) in which the grooves 551 (shown in FIG. 4) having a mesh shape is formed in an oblique direction. use. If the groove 551 is not formed in an oblique direction and is orthogonal to the rotation direction of the gravure roll 55, the paste composition 10a which is a raw material of the electromagnetic shielding member 10 accommodated in the groove 551 (Fig. 4). Is not well away from the groove 551. That is, since the paste composition 10a is not affected by the rotational force of the gravure roll 55, it is not easy to drop the paste composition 10a from the gravure roll 55.

On the other hand, when the rotation direction of the gravure roll 55 and the direction in which the grooves 551 extend coincide with each other, the paste composition 10a may be well separated from the grooves 551 by the rotational force of the gravure roll 55. Therefore, when the groove 551 is formed in a direction coinciding with the rotation direction of the gravure roll 55, the electromagnetic shielding member 10 having the opening 109 having a uniform size may be formed.

More specifically, when the groove is formed only in the direction coinciding with the rotation direction of the gravure roll, it is impossible to form the shield member in the form of a mesh. That is, the mesh shape may have a rectangular shape, and since the groove must be formed in a direction orthogonal to the rotation direction of the gravure roll, it is difficult to transfer the paste composition to the blanket roll.

As shown in the enlarged circle of FIG. 2, when the electromagnetic shielding member 10 is formed on the tin surface of the transparent tempered glass substrate 20 using the above-described method, the first shielding portion 101 is in the x-axis direction. And a constant angle α2 is formed. Here, the angle α2 is an angle formed between the tangential line formed by the gravure roll and the blanket roll and the first groove, and may be 20 ° to 70 °. If the angle α2 is too small or too large, the first shielding portion 101 and the second shielding portion 103 may be densely packed to reduce the electromagnetic shielding effect. In addition, when the electromagnetic wave shielding filter 100 is used in the display device 200 (shown in FIG. 7), the moiré shape may be formed while overlapping the black layer 651 of the display device 200. More specifically, the angle α2 may be 35 ° to 55 °.

As shown in the enlarged source of FIG. 2, the resolution of the image can be increased by forming a smaller width W of the electromagnetic shielding member 10 to maximize the area of the opening 109. To this end, the width W of the electromagnetic shielding member 10 may be greater than 0 and 50 μm or less. In this case, the electromagnetic wave shielding member 10 cannot be observed by the naked eye. When the width W of the electromagnetic wave shielding member 10 is too large, the size of the opening 109 becomes small and the resolution of the image is lowered. More specifically, the width W of the electromagnetic shielding member 10 is preferably 15 μm to 30 μm.

On the other hand, the average pitch P of the electromagnetic wave shielding member 10 can be larger than 0 and 500 micrometers or less. If the average pitch P of the electromagnetic shielding member 10 is too large, the electromagnetic shielding member 10 is not formed densely, and thus electromagnetic waves may be emitted to the outside without being absorbed. As a result, the electromagnetic shielding effect is lowered. In more detail, it is preferable that the average pitch P of the shielding member 10 is 200 micrometers-400 micrometers.

The electromagnetic shielding member 10 may include a conductive metal to maximize the electromagnetic shielding effect. Since the conductive metal can collect electromagnetic waves passing through the electromagnetic shielding filter 100, the electromagnetic shielding effect is excellent. Silver, copper, nickel, tin, or an alloy thereof can be used as the conductive metal. Since the conductive metals are excellent in electrical conductivity, they can effectively shield electromagnetic waves.

3 is a partial cross-sectional view of the electromagnetic wave shielding filter 100 taken along the line II-II of FIG. 2.

As shown in FIG. 3, the electromagnetic shielding member 10 has a tin surface 23 on the transparent tempered glass substrate 20 and an air surface 25 on the lower portion. And an upper portion of the tin layer 23 and an edge layer 30 formed at an edge of the upper tin surface. Since the edge layer 30 includes black ceramic, the appearance of the electromagnetic wave shielding filter 100 may be improved. In addition, the edge layer 30 may effectively connect the ground member 40 to the electromagnetic shielding member 10. The thickness of the edge layer 30 may be about 15 μm to 20 μm. The ground member 40 prints the paste composition on the tin layer 23 on the transparent tempered glass substrate 20 and on the edge layer 30 formed on the tin surface 23 by an offset method, thereby shielding the electromagnetic wave shield member 10. After forming a, the ground member 40 is formed thereon. As the ground member 40, a conductive film tape can be used. Thereafter, the color correction and near-infrared blocking layer 50 and the anti-reflection layer 60 are formed under the air surface 25.

FIG. 4 schematically illustrates a process of manufacturing the electromagnetic wave shielding filter 100 of FIG. 2. The electromagnetic wave shielding filter 100 may be manufactured using the offset printing apparatus 500. Hereinafter, the offset printing method will be described in detail.

As shown in FIG. 4, the offset printing apparatus 500 includes a dispenser 51, a doctor 53, a gravure roll 55, and a blanket roll 57. The offset printing method uses the offset printing apparatus 500 and includes an off process and a set process. In the off process, the paste composition 10a is removed from the gravure roll 55. In the set process, the removed paste composition 10a is applied onto the substrate 20. The dispenser 51 discharges the paste composition 10a at predetermined time intervals. The paste composition 10a discharged from the dispenser 51 is accommodated in the groove 551 formed in the gravure roll 55. As described above, the paste composition 10a may include an organic substance having elasticity, a conductive metal, a solvent, a binder, a predetermined dispersant, and the like. As a solvent, an organic solvent having a boiling point of 200 ° C. or more and an organic solvent having a boiling point of less than 200 ° C. may be used together, and a glass powder, that is, glass frit may be used as the binder. The organic material may include conventional acrylate resins, polyesters, polyurethanes, oligomers, monomers and the like. The solvent and the organic material may be removed in the process of baking the substrate 20. The paste composition 10a further contains a black pigment and a predetermined dispersant.

Since the amount of paste composition 10a contained in the groove 551 is large, the paste composition 50a may overflow to the outside of the groove 551. Therefore, the paste composition 10a overflowed by the doctor 53 is removed while rotating the gravure roll 55 in the arrow direction (counterclockwise direction). Since the doctor 53 is in contact with the outer surface of the gravure roll 55, the paste composition 10a overflowed to the outside of the groove 551 can be efficiently removed. Therefore, the paste composition 10a can be appropriately filled in the groove 551 of the gravure roll 55 without overflowing.

The blanket roll 57 is located opposite the gravure roll 55. The blanket roll 57 rotates in the direction opposite to the rotation direction of the gravure roll 55 (clockwise). As a result, the paste composition 10a contained in the groove 551 is transferred onto the blanket roll 57 while the gravure roll 55 meets the blanket roll 57. Therefore, the paste composition 10a adheres to the outer surface of the blanket roll 57.

The blanket roll 57 applies the paste composition 10a onto the transparent tempered glass substrate 20 while moving on the transparent tempered glass substrate 20 described above in the direction of the arrow. The transparent tempered glass substrate 20 is washed and prepared. Accordingly, a paste composition 10a in the form of a mesh for forming the electromagnetic shielding member 10 (shown in FIG. 2) is formed on the tin surface of the transparent tempered glass substrate 20. At this time, the transparent tempered glass substrate is produced by reinforcing the plate glass manufactured by the plot method, in the present invention is to paste the paste composition on the tin surface by dividing it into the tin surface and the air surface, in the drawing for convenience on the glass substrate 20 The comment surface of is not shown. Through such printing, the printed layer is exposed to the outside air in the filter final product, and the printed layer is directed to the panel portion of the display element.

Next, the solvent and organic substances contained in the paste composition 10a are removed by placing the substrate 20 in a heating furnace (not shown) and heating it. The paste composition 10a may be dried before this firing process. Moreover, the electromagnetic wave shielding member can also be directly formed by heating the transparent tempered glass substrate 20 and removing a solvent and organic substance. That is, the electromagnetic wave shielding filter is directly manufactured without performing a separate process such as etching the paste composition 10a. Therefore, since the present invention is a simple process, it is possible to reduce the manufacturing cost of the electromagnetic shielding filter.

In addition, in the firing process, the temperature is preferably 500 to 540 ° C., and the substrate is held at the temperature for 10 to 30 minutes during firing and then slowly cooled. At this time, the higher the firing temperature is, the stronger the tempered unwinding of the tempered glass substrate is, so that the impact resistance is weakened. In addition, as the firing temperature is higher, the degree of migration of the conductive metal particles in the electromagnetic shielding member reacts with the tin layer, resulting in a greater yellowishness. In other words, if the firing temperature is too high, the degree of yellowing becomes severe and color correction becomes difficult when the filter is commercialized. Therefore, it is necessary to lower the temperature to an appropriate range in order to reduce yellowing. Therefore, the present invention can also appropriately adjust the resistance value and the optical properties by adjusting the firing temperature in the tin surface printing in the appropriate range as described above.

Other details of the offset printing method in the present invention can be easily understood by those of ordinary skill in the art, the detailed description thereof will be omitted.

When manufacturing the electromagnetic wave shielding filter using the photolithography method instead of the offset printing method, the copper foil is first adhered to the resin film. Next, a dry film resist is laminated on copper foil, and exposure, image development, an etching, a peeling process, etc. are performed in order to form a pattern. Therefore, the manufacturing process is complicated and the productivity is not good.

In addition, the present invention is formed by laminating the color correction and near-infrared blocking layer 50 and the anti-reflective layer 60 on the opposite surface of the printed layer in order to act as an electromagnetic wave filter, in which the formation method is made by a conventional method, The detailed description is omitted.

5 is a cross-sectional view showing the configuration of the electromagnetic shielding filter according to the present invention manufactured by the above method. 6 is an electron micrograph showing a mesh pattern of the electromagnetic shielding filter according to the present invention.

As shown in FIG. 5, the electromagnetic wave shielding filter of the present invention is divided into a tin surface 23 and an air surface 25 on the transparent tempered glass substrate 20, and the paste composition 10a is disposed on the tin surface 23. Is formed, the lower surface of the glass substrate 20 to protect the air surface 25, for the function as a filter, the color correction and near-infrared blocking layer 50 and the anti-reflection layer 60, which is an optical functional layer is formed do. In the present invention, a glass substrate printed on the tin surface is directly provided, so that the PET film and the adhesive layer are excluded from the film mesh like the conventional Cu mesh when the optical functional layers are compared, thereby providing optical characteristics ( Transparency and simplification of the structure to simplify the process. In addition, in the printing filter of the present invention, the printed layer is directed to the panel portion when applied to the panel, and the film layers 50 and 60 have a structure exposed to the outside.

On the other hand, in the case of manufacturing the electromagnetic shielding filter using a plating method, a pattern must be formed on a resin film and copper should be plated to obtain a desired electrical conductivity. However, waste liquid generated during plating causes environmental pollution.

The above-described photolithography method or plating method cannot form a pattern directly on a substrate. For example, the plating method is carried out by winding the base material in the form of a roll and immersing it in a plating bath. Since the substrate cannot be wound in the form of a roll, it is impossible to form an electromagnetic shielding member by plating the substrate. In addition, when the substrate is used, the process is complicated because the pattern must be adhered to the substrate. The offset printing method can solve the above problem. That is, in the offset printing method, since the electromagnetic shielding member 10 is formed directly on the tin surface of the transparent tempered glass substrate 20, the process may be simplified to reduce the manufacturing cost. In addition, in the offset printing method, no harmful substances are discharged, and thus no pollution is caused.

FIG. 7 schematically illustrates a display device 200 including the filter 100 for shielding electromagnetic waves of FIG. 2. In the enlarged circle of FIG. 7, the display device 200 viewed in the z-axis direction is enlarged.

As shown in FIG. 7, the electromagnetic shielding filter 100 is fixed on the display panel 600 (shown in FIG. 8) by using the fixing member 110. Therefore, the electromagnetic wave shielding filter 100 may be stably stored in the display device 200.

As shown in the enlarged circle of FIG. 7, the electromagnetic shielding member 10 is positioned on the black layer 651 included in the display panel 600 (shown in FIG. 8). In addition, the black layer 651 is positioned between the first substrate 610 and the second substrate 620 of the display panel. Although not shown in the enlarged source of FIG. 7, a second substrate 620 (shown in FIG. 8) is positioned between the electromagnetic shielding member 10 and the black layer 651, and the electromagnetic shielding member 10 is provided. The glass member 20 (shown in FIG. 8) is located above.

The electromagnetic shielding member 10 shields electromagnetic waves emitted from the display panel 600.

As shown in the enlarged circle of FIG. 7, the electromagnetic shielding member 10 has a rhombus-shaped opening 109. Although not shown in FIG. 7, the electromagnetic shielding member 10 is preferably substantially square. In this case, the electromagnetic shielding effect may be maximized by optimizing the shape of the electromagnetic shielding member 10.

The lengths of the four sides forming the opening 109 are substantially the same. Since the lengths of the four sides are substantially the same, the shape of the electromagnetic shielding member 10 is regular. As a result, since the intensity of light emitted through the opening 109 is uniform, a uniform image can be displayed. On the other hand, although the opening 109 is shown in a rhombus shape in the enlarged circle of FIG. 7, this is merely to illustrate the present invention, and the present invention is not limited thereto. Therefore, the opening part 109 should just be polygonal shape.

The electromagnetic shielding member 10 is formed by an offset printing method by shielding portions that cross each other. Therefore, the width of the electromagnetic shielding member 10 becomes slightly thick at the intersection where the shields meet each other. As a result, the opening 109 has a chamfered shape. That is, since the width of the electromagnetic shielding member 10 is slightly increased at the intersection of the electromagnetic shielding member 10, the opening 109 has a shape in which the edge is eliminated. Due to the shape of the opening 109, the electromagnetic shielding member 10 is continuously formed without breaking, and thus electromagnetic waves may be shielded over the entire surface of the electromagnetic shielding member 10.

As shown in the enlarged circle of FIG. 7, the electromagnetic shielding member 10 is formed while three-dimensionally crossing the black layer 651. Therefore, the phenomenon of image blur can be prevented. Furthermore, since the electromagnetic wave shielding member 10 has a width so small that it is difficult to recognize with the naked eye, it has little influence on image quality. Therefore, as shown in the enlarged circle of FIG. 7, even if the electromagnetic shielding member 10 is located on the black layer 651, an image having high resolution can be displayed.

8 is a partial cross-sectional view taken along the line V-V of FIG. 7.

8 illustrates a plasma display panel as the display panel 600. The plasma display panel shown in FIG. 8 is merely for illustrating the present invention, but the present invention is not limited thereto. Therefore, other display panels requiring an electromagnetic shielding filter can be used.

The display panel 600 includes a first substrate 610, a second substrate 620, a display electrode 680, an address electrode 640, a partition 660, a phosphor layer 670, a dielectric layer 630, and a protective film ( 635 and black layer 651. The inside of the display panel 600 is filled with discharge gas. The first substrate 610 and the second substrate 620 face each other. The partition wall 660 forms a plurality of discharge cells, and a phosphor layer is formed inside the discharge cell. The dielectric layer 630 protects the address electrode 640 and the display electrode 680 from electrons. The passivation layer 635 protects the dielectric layer 630 disposed thereon.

When a voltage is applied to the address electrode 640 and the display electrode 680, a discharge occurs between the address electrode 640 and the display electrode 680. Ultraviolet rays generated by the discharge impinge on the phosphor layer 670 and the visible light is emitted from the phosphor layer 670. Meanwhile, a black layer 651 is formed on the partition wall 660 to improve contrast ratio. The black layer 651 is positioned between the first substrate 610 and the second substrate 620. Since the black layer 651 is formed on the partition wall 660 where the light is not emitted, the loss of the light emitted from the phosphor layer 670 may be reduced. More specifically, the black layer 651 may be formed in contact with the partition 660 as shown in FIG. 8 or may be formed on the dielectric layer 630 on the partition 660 as another example.

As shown in FIG. 8, the electromagnetic shielding filter 100 is positioned on the display panel 600. Accordingly, the electromagnetic wave shielding filter 100 may shield electromagnetic waves emitted from the display panel 600. Since the electromagnetic shielding member 10 faces the second substrate 620, the electromagnetic shielding member 10 is not exposed to the outside. Therefore, it is possible to prevent the electromagnetic wave shielding member 10 from being damaged and to prevent the appearance deterioration due to the electromagnetic shielding member 10. In addition, only the optical function layer including the color correction and near infrared ray blocking layer 50 and the anti-reflection layer 60 is exposed to the outside.

On the other hand, when the thickness of the first substrate 610 and the second substrate 620 is small, the display panel 600 is weak to external impact. Therefore, the strength of the display device 200 is reinforced by using the electromagnetic wave shielding filter 100 including the substrate 20. That is, since the thickness of the electromagnetic wave shielding filter 100 is included in the thickness of the display device 200, the display device 200 becomes thick and very strong against external impact. For example, by forming the thickness t20 of the substrate 20 larger than the thickness t620 of the second substrate 620, the durability of the display device 200 may be improved by the electromagnetic wave shielding filter 100. have.

As described above, the present invention prints the paste composition on the transparent tempered glass substrate tin surface in the process of manufacturing the electromagnetic shielding filter through the offset printing process, by the appropriate yellowing phenomenon of the conductive metal in the tin surface and the electromagnetic shielding member The effect of reducing external light reflection and improving blackness can also be achieved, and the moisture resistance problem can be minimized even when the printed layer is exposed to outside air in the final product.

Therefore, the present invention makes it possible to provide an electromagnetic shielding filter having a uniform shape, line width and thickness of the mesh pattern and excellent quality. In addition, the electromagnetic shielding filter may be applied to a display device to further improve appearance characteristics.

In addition, the present invention can produce a filter for electromagnetic shielding in a continuous process by using an offset printing method is simple and cheap manufacturing process compared to other processes.

In addition, when the display device including the electromagnetic wave shielding filter having excellent appearance quality is manufactured, the electromagnetic wave shielding effect of the display device can be maximized.

Hereinafter, the present invention will be described in more detail through experimental examples. These examples are only for illustrating the present invention, and the present invention is not limited thereto.

Production Example

A solvent, a glass powder, a conductive metal, a black pigment and a dispersant were stirred at room temperature in an acrylate polymer resin with the following composition and content, and finally, a black conductive paste composition for gravure offset printing was prepared using a 3-roll mill.

66.7% by weight of acrylate polymer resin and monomer mixed in a weight ratio of 33.3, 7% by weight of butylcatbitol acetate (BCA), 2.2% by weight of diethylene glycol methylethyl ether, 0.3 wt% of dispersant, and conductive metal A black conductive paste was prepared including 75 wt%, black powder 5.5 wt% and glass powder 4 wt%.

Here, the acrylate polymer resin has a weight average molecular weight of 15,000, and methyl acrylate (methylacrylate, MA), BM (butyl methacrylate, butyl methacrylate), HEMA (hydroxyethyl methacrylate, hydroxyethyl methacrylate), and MMA (methylmethacrylate). , Methyl methacrylate) is copolymerized in parts by weight of 30: 40: 10: 20, respectively.

The monomer is trimethylolpropane triacrylate modified ethylene oxide.

The dispersant is a block copolymer containing a base pigment affinity group, which is DISPERBYK-2050 manufactured by BYK. The conductive metal is spherical silver powder and the average particle size is 1.5 mu m. The black pigment is Co. As the glass powder, Bi ₂ O ₃ -based glass powder was used.

Example

(Formation of electromagnetic shielding filter)

Gravure offset printing was performed using the paste composition prepared in Preparation Example to meet the pattern specifications used for the electromagnetic shielding filter.

That is, the paste composition was printed in a mesh form on the tin surface of the transparent tempered glass substrate using the same offset printing apparatus as that shown in FIG. 4. In this case, the line width of the mesh pattern was 25㎛, the pattern specification pitch was 270㎛.

Next, in the firing process, the paste composition formed on the tin surface of the transparent tempered glass substrate was maintained at 500 to 540 ° C. for 20 minutes to form an electromagnetic shielding filter mesh pattern.

Comparative example

(Formation of electromagnetic shielding filter)

A mesh pattern was formed on the air surface of the transparent tempered glass substrate using the same composition as in Example, and the firing process was performed at the same temperature to form a mesh pattern for an electromagnetic shielding filter.

Experimental Example

(Characteristic Evaluation of Electromagnetic Shielding Filter)

Optical values such as blackness and yellowing of the electromagnetic wave shielding filter of Examples and Comparative Examples were compared and evaluated based on the following criteria, and the results are shown in Table 1 below. The optical value difference test according to each substrate surface was carried out in total 6lots, and printed 30 times for each lot and averaged. In addition, the durability of the electromagnetic shielding mesh printed matter of the Examples and Comparative Examples was evaluated, the evaluation criteria were as follows.

(Optical characteristic evaluation criteria)

Black light (L), yellowing (b), total reflection (SCI Y), diffuse reflection by irradiating the D65 light source in contact with the opposite side of the printing surface of the transparent tempered glass substrate printed / fired under the white light source conditions (SCE Y) values were measured 3 points per sample and averaged 30 pieces per lot (6 lots in total). The instrument used for the measurement was a spectrophotometer (Model Minolta CM2600d).

(Moisture resistance evaluation standard)

The protective film was attached to the printed opposite surface of the formed mesh pattern substrate and left to stand at constant temperature and humidity. The optical value change and appearance change were evaluated after removing the protective film.

That is, in the following constant temperature and humidity conditions, the samples of the Examples and Comparative Examples were left to compare and evaluate the change of the optical value and the appearance change, and the optical value change of the Example is shown in Table 2. Transmitted color coordinates and reflectance were measured by UN / VIS / NIR spectrophotometer (model name Hitachi U4100) as optical values were changed, and transmittance and haze were measured by a turbidimeter (model name Nippon Denshoku NDH).

* Constant temperature / humidity condition: 60 ° C, 90% RH, 1000 h

* Moisture resistance ○: Appearance change X / Transmitted color coordinate change ± 0.01 / Transmittance change within 10%

 TABLE 1

Comparative example Example L black 37.51 35.26 B yellowing 0.40 2.92 SCI Y 9.81 8.69 SCE Y 1.76 0.80 Cloudiness Occurrence ○ Occurrence X (moisture resistance ○)

TABLE 2

0hr 250hr 500hr 1000hr Transmittance% 79.5 79.8 79.6 79.6 Transmission color coordinate x: 0.312 y: 0.331 x: 0.312 y: 0.331 x: 0.312 y: 0.330 x: 0.312 y: 0.331 reflectivity% 10.6 10.5 10.5 10.6 Haze 2.7 2.8 2.8 2.8

Through the results of Table 1, in the case of the embodiment of printing the paste composition on the tin surface, compared to the comparative example of printing the paste composition on the air surface, it showed a decrease in the blackness value (L), a decrease in the reflection value (Y) . This is to confirm that the tin surface printing and firing can cause the yellowing of the glass substrate to be relatively more effective to reduce the blackness and reflection value. Therefore, the method according to the present invention can be used to lower the optical value by causing proper yellowing at an appropriate firing temperature through tinplate printing. In addition, when printing on the air surface, white turbidity occurred, while it was confirmed that there was almost no change in appearance characteristics and characteristic values when printing on the tin surface.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and a person skilled in the art does not depart from the spirit and scope of the present invention described in the above-described range and the appended claims. It will be appreciated that various changes and modifications can be made within the scope of the invention.

1A is a schematic process diagram of a manufacturing process of a conventional electromagnetic shielding filter.

FIG. 1B is an electron micrograph showing a Cu mesh pattern formed by the method of FIG. 1A.

2 is a schematic perspective view of an electromagnetic shielding filter according to an embodiment of the present invention.

3 is a partial cross-sectional view taken along the line II-II of FIG. 2.

4 is a schematic diagram illustrating a method of manufacturing the electromagnetic shielding filter of FIG. 2.

5 is a cross-sectional view showing the configuration of the electromagnetic shielding filter according to the present invention manufactured by the above method.

6 is an electron micrograph showing a mesh pattern of the electromagnetic shielding filter according to the present invention.

FIG. 7 is a schematic perspective view of a display device including the filter for shielding electromagnetic waves of FIG. 2.

FIG. 8 is a partial cross-sectional view taken along the line V-V of FIG. 4.

Claims (34)

A transparent tempered glass substrate having an air surface having a relatively small tin distribution on one side, and an air surface having a relatively small tin distribution on the other side, and An electromagnetic shielding filter comprising an electromagnetic shielding member formed in a mesh form on a tin surface of the transparent tempered glass substrate. The method of claim 1, wherein the transparent tempered glass substrate is made by reinforcing the plate glass produced by a float (float) method, The plot method comprises the step of producing a plate glass in a state in which the suspended glass is floating in the tin while flowing the molten glass to the molten metal tin, filter for electromagnetic shielding. According to claim 1, Color correction and near-infrared blocking layer sequentially formed in the lower portion of the air surface of the transparent tempered glass substrate; And an antireflection layer. The filter for shielding electromagnetic waves according to claim 3, wherein the near-infrared blocking layer comprises a near-infrared shielding dye having a near infrared absorption function of 850 to 1250 nm, and a selective light absorbing material for neon wavelength blocking and color correction. The method of claim 4, wherein the near-infrared shielding pigment comprises a material selected from the group consisting of nickel complex, phthalocyanine, cyanine, dimonium compounds, and mixtures thereof, The selective light absorbing material for blocking the neon wavelength and color correction is an electromagnetic wave shield filter comprising at least one material selected from the group consisting of azo, stryl, cyanine, anthraquinone and tetraazapopyrine compounds. The filter of claim 4, wherein the anti-reflection layer comprises a low refractive index layer including a low refractive index material and a high refractive index layer including a high refractive index material. The method of claim 6, wherein the low refractive index material comprises at least one material selected from the group consisting of fluorine-based compounds, silicon oxide, magnesium fluoride and aluminum oxide, The high refractive index material comprises one or more inorganic fine particles selected from the group consisting of titanium dioxide, indium tin oxide, zinc oxide, antimony, tin oxide, cerium oxide, zirconium oxide and antimony oxide. The method of claim 1, wherein the electromagnetic shielding member, At least one first shield extending in one direction, And at least one second shield intersecting the first shield. The method of claim 1, The electromagnetic shielding member has an polygonal opening, the opening is chamfered filter. The method of claim 1, And an edge layer formed along an edge of the transparent tempered glass substrate, wherein the electromagnetic shielding member is formed on the edge layer. The method of claim 10, And a grounding member connected to an end of the electromagnetic shielding member to ground the electromagnetic shielding member. The filter for electromagnetic shielding according to claim 1, wherein the electromagnetic shielding member is formed by offset printing and baking a black conductive paste composition on a tin surface of the transparent tempered glass substrate. The method of claim 12, wherein the black conductive paste composition An electromagnetic wave shielding filter comprising a) an acrylate polymer resin and an oligomer or monomer, b) a solvent, d) a glass powder, e) a conductive metal, and f) a black pigment. The method of claim 13, wherein the acrylate polymer resin and oligomer or monomer 5 to 15 parts by weight, solvent 5 to 15 parts by weight, glass powder 1 to 10 parts by weight, conductive metal 50 to 90 parts by weight and black pigment 1 to 10 parts by weight Electromagnetic shielding filter comprising. The filter of claim 13, wherein the composition further comprises 0.05 to 1 parts by weight of a dispersant. The filter of claim 13, wherein the black pigment comprises a cobalt, copper, rudenium, manganese, nickel, chromium, or iron-based compound. The filter of claim 16, wherein the black pigment further comprises an auxiliary pigment of copper, rudenium, manganese, nickel, chromium, or iron. The filter of claim 13, wherein the acrylate polymer resin has a weight average molecular weight of 5,000 to 100,000. The filter for electromagnetic wave shield according to claim 13, wherein the solvent comprises at least one or more types of high boiling point solvents having a boiling point of 200 ° C or more and at least one or more types of low boiling point solvents having a boiling point of less than 200 ° C. The glass powder according to claim 13, wherein the glass powder comprises a Pb-based powder, a Pb-free powder, a colored glass powder prepared by mixing black or colored pigments, and a glass powder containing a colored component of V ₂ O ₅ . Electromagnetic shielding filter that is selected from one or more kinds from the group. The filter for shielding electromagnetic waves according to claim 10, wherein the conductive metal is a metal powder for an electrode selected from the group consisting of silver, copper, nickel, tin, and alloys thereof. Providing a grooved gravure roll in the form of a mesh, Filling the groove with a black conductive paste composition; Providing a blanket roll facing the gravure roll and rotating in a direction opposite to the direction of rotation of the gravure roll, Transferring the conductive paste composition to the blanket roll while rotating the gravure roll, Providing a transparent tempered glass substrate having a tin surface on one side, the tin surface having a relatively large amount of tin distributed, and having an air surface having a relatively small amount of tin distributed on the other side, Applying the conductive paste composition onto the tin surface of the transparent tempered glass substrate while the blanket roll moves over the transparent tempered glass substrate, and Baking the conductive paste composition to form a shielding member formed of a single layer shielding electromagnetic waves on the tin surface of the transparent tempered glass substrate. Method of manufacturing a filter for electromagnetic shield comprising a. The method of claim 22, wherein the transparent tempered glass substrate is manufactured by reinforcing a plate glass manufactured by a float method. The method of claim 22, In the step of providing the gravure roll, the groove, At least one first groove extending in one direction, and At least one second groove that intersects the first groove Method of manufacturing a filter for electromagnetic shield comprising a. The method of claim 24, The one or more first grooves include a plurality of first grooves, and the average pitch of the plurality of first grooves is greater than 0 and 500 μm or less. The method of claim 25, The average pitch of the plurality of first grooves is 200㎛ 400㎛ manufacturing method of the filter for shielding. The method of claim 24, The groove is a method of manufacturing an electromagnetic shielding filter extending in an oblique direction. The method of claim 24, The angle formed by the tangent formed by the gravure roll and the blanket roll to meet the first groove portion is 20 ° to 70 ° manufacturing method of the filter for electromagnetic shielding. A transparent tempered glass substrate having an air surface having a relatively small amount of tin on one side, and a tin surface having a relatively low amount of tin on the other side, An electromagnetic shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate, and A display device which displays an image and includes a display panel facing the transparent tempered glass substrate. And said electromagnetic shielding member is applied to shield electromagnetic waves emitted from said display panel, and is formed by offset printing and baking a black conductive paste composition on a tin surface of a transparent tempered glass substrate. The display device of claim 29, wherein the transparent tempered glass substrate is manufactured by reinforcing a plate glass manufactured by a float method. 30. The method of claim 29, wherein the lower portion of the transparent tempered glass substrate air surface sequentially formed to expose to the outside air; Color correction and near infrared blocking layer; And an antireflection layer. The method of claim 29, The display panel, A first substrate and a second substrate facing each other, and A black layer positioned between the first substrate and the second substrate Including, And the electromagnetic shielding member is three-dimensionally intersected with the black layer. The method of claim 29, And the electromagnetic shielding member is in contact with the second substrate. The method of claim 29, The display panel is a plasma display panel.

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