JP2009295980A - Electromagnetic wave shielding filter and its manufacturing method, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic wave shielding filter and a display device having it. <P>SOLUTION: The electromagnetic wave shielding filter includes: a transparent tempered glass substrate having a relatively large amount of tin diffusion on one surface surfaces, and having a relatively less amount of tin diffusion on another air surface as compared with the tin surface; and an electromagnetic shielding member formed in a mesh shape on the tin surface of the transparent tempered glass substrate. The electromagnetic shielding filter is applied to shield a plasma display panel from an electromagnetic wave, an effect of an outside light reflection reduction and blackness improvement effect can be made by a suitable yellowing of conductive metal in the tin surface and electromagnetic shielding member, and the problem of moisture resistance can be minimized even if the printed layer of the final product is exposed to the atmosphere. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is applied to an electromagnetic wave shielding filter of a display device such as a plasma display panel to improve pattern quality, printability, and continuous process, and in particular, has excellent optical characteristics of a plasma display and has a printing surface. The present invention relates to an electromagnetic wave shielding filter that can have moisture resistance even when exposed to the outside air, a manufacturing method thereof, and a display device including the same.

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

  On the other hand, EMI (electromagnetic interference) is emitted from a large number of electronic elements included in the display device. EMI may cause malfunction of the display device or cause harm to the human body. Therefore, an electromagnetic wave shielding filter is attached to the display device so as to shield EMI.

  In addition to blocking electromagnetic waves, the electromagnetic wave shielding filter corrects color, reduces external light reflection and prevents near-infrared rays to prevent remote control malfunction, protects the module from external impacts, Scattering can be prevented.

As shown in FIG. 1a, a conventional electromagnetic shielding filter manufacturing method generally forms an EMI mesh pattern through a lamination process, an exposure and development process, an etching process, and a strip process using a Cu substrate in the usual manner. Has been done. The EMI filter formed by the above method includes a pressure sensitive adhesive layer (PSA) on a glass substrate and a Cu mesh pattern on the top of the substrate on which a PET film is formed, and a near infrared layer (Near Infrared, hereinafter) NIR), a color correction layer, and an anti-reflection layer (hereinafter referred to as AR) are provided, and usually a double-sided laminated form of functional layers and a Cu mesh on the basis of a base substrate. The Cu mesh pattern formed by the above method can have a form as shown in FIG. At this time, the position of the optical functional layer can be changed as necessary, as different from the drawing. For example, the NIR and color correction layer and the AR layer may be formed on both sides of the PET film with a substrate including the PET film. However, the existing film mesh type such as Cu mesh has a problem that the process is complicated because both sides are laminated at the time of manufacturing the filter and the transparent process must be further advanced to satisfy the optical characteristics.
In addition, in the method of manufacturing an electromagnetic wave shielding filter using an offset process, after printing and baking a conductive paste on the air surface (air surface) of a glass substrate, an antireflection layer, color correction, and near When the transparentization process is performed after the infrared layer or the like is configured, the entire printed layer (Air surface) of the filter can be exposed to the outside air in the final product. In such a case, there is a problem that the glass substrate is blurred due to white turbidity due to weak moisture resistance and the product quality and optical characteristics are deteriorated. Therefore, the method requires the functional film to be laminated on both sides for protecting the printing surface, but the double-sided lamination causes a problem that the process becomes complicated.

  In the present invention, an electromagnetic wave shielding layer is formed directly on the tin surface (tin surface) of the transparent tempered glass substrate by applying an offset process, and a functional film is formed by cross-sectional lamination on the air surface (Air surface) which is the opposite surface. Thus, an electromagnetic wave shielding filter capable of having excellent display optical characteristics and having moisture resistance and a method for producing the same are provided. The present invention also provides a display device including the electromagnetic wave shielding filter.

The present invention
A transparent tempered glass substrate having a tin surface with a relatively large amount of tin distribution on one surface and an air surface with a relatively small amount of tin distribution compared to the tin surface on the other surface, and the transparent tempered glass substrate An electromagnetic wave shielding filter including an electromagnetic wave shielding member formed in a mesh shape on a tin surface of the present invention is provided.
The transparent tempered glass substrate is manufactured by strengthening a plate glass manufactured by a float method, and is divided into a tin surface (tin surface) and an air surface (Air surface) in the present invention. It is printed.

  The air surface, which is the printing opposite surface of the transparent tempered glass substrate, may further include a color correction and near-infrared shielding layer sequentially formed; and an antireflection layer. In other words, the color correction and near-infrared blocking layer is a glass substrate including a film such as PET in the lower part, and is formed on both sides of the film or formed on one side of the film and then laminated. Used.

  The color correction and near-infrared blocking layer may include a near-infrared shielding dye having a near-infrared absorption function with a wavelength of 850 to 1250 nm and a selective light-absorbing material for neon wavelength blocking and color correction. The near-infrared shielding dye may include one or more substances selected from the group consisting of nickel complex-based, phthalocyanine-based, cyanine-based, diimonium-based, and mixtures thereof. The selective light-absorbing material for blocking the neon wavelength and correcting the color may include one or more materials selected from the group consisting of azo, styryl, cyanine, anthraquinone, and tetraazapopirin. The near-infrared blocking layer and the color correction layer are manufactured by mixing the above-mentioned near-infrared absorbing material and the selective light-absorbing material in a polymer resin and a solvent, and coating the transparent substrate such as a glass substrate including a film. Can do.

  The antireflection layer may include a low refractive layer including a low refractive index material and a high refractive layer including a high refractive index material. The low refractive index material may include one or more materials selected from the group consisting of fluorine-based materials, silicon oxide, magnesium fluoride, aluminum oxide, and the like. The high refractive index substance includes at least one substance 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. Can do. The antireflection layer may be formed by forming a hard coating layer on a substrate and alternately coating a coating solution containing a high refractive index material and a coating solution containing a low refractive index material on the hard coating layer. .

  The electromagnetic wave shielding member is preferably formed by printing and baking a black conductive paste composition on the substrate. At this time, the black conductive paste composition is an electromagnetic shielding filter paste composition applied to a display device such as a plasma display panel, and preferably the black conductive paste composition is printed on a glass substrate (for example, , Offset printing) and firing to provide the electromagnetic wave shielding filter for a display device.

  The black conductive paste composition comprises acrylate polymer resin and monomer or oligomer 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 Or 10 parts by weight. In addition, the paste composition of the present invention preferably further includes 0.05 to 1 part by weight of a dispersant.

The present invention also provides:
Providing a gravure roll having a mesh-shaped groove formed thereon;
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 an air surface on one side including a relatively large amount of tin distribution and a relatively small amount of tin distribution on the other side compared to the tin surface;
A step of applying the conductive paste composition onto a tin surface of the transparent tempered glass substrate while the blanket roll moves on the transparent tempered glass substrate; and baking the conductive paste composition to form the transparent tempered glass. An electromagnetic wave shielding filter manufacturing method including a step of forming a single-layer shielding member that shields electromagnetic waves on a tin surface of a substrate is provided.

  In providing the gravure roll, the groove preferably includes one or more first groove portions extending in one direction and one or more second groove portions intersecting the first groove portion. Preferably, the one or more first groove portions include a plurality of first groove portions, and an average pitch of the plurality of first groove portions is greater than 0 and equal to or less than 500 μm. The average pitch of the plurality of first grooves may be 200 μm to 400 μm. The groove extends in a diagonal direction, and an angle formed between a tangent formed by the gravure roll and the blanket roll and the first groove may be 20 ° to 70 °.

The present invention also provides a transparent tempered glass substrate, an electromagnetic wave shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate, and an image, and a display panel facing the transparent tempered glass substrate Including
The electromagnetic wave shielding member is applied to shield electromagnetic waves emitted from the 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. Providing equipment.

  Hereinafter, the present invention will be described in detail.

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

  First, as the “transparent tempered glass substrate” in the present invention, a transparent tempered glass substrate obtained by strengthening a plate glass manufactured by a float method by a usual method is used. In addition, in the manufacturing process of the plate glass, the surface that comes into contact with the molten metal (tin) is defined as a tin surface (tin surface), and the opposite surface is divided into an air surface (air surface) for printing / firing. To do.

  At this time, the tin surface (tin surface) in the present invention means a surface in which a predetermined amount of tin is distributed on the transparent tempered glass substrate, and means a surface having a relatively large amount of tin distribution. The surface which contacts air on the opposite side of the tin surface and has a relatively small amount of tin distribution compared to the tin surface.

  That is, in the transparent tempered glass reinforced with the plate glass manufactured by the float method, when the light source is illuminated using a tin detector in a dark room condition, the irradiated light is diffused and relatively blurred. The surface that looks like this is defined as the tin surface, and the layer that appears relatively transparent is divided into the air surface and applied to the offset process.

  As a result of the experiments by 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, the product has a filter structure in which the printing surface is exposed. Found that is possible. In other words, unlike the existing film products such as Cu mesh, the method as described above forms an electromagnetic wave shielding mesh directly on the glass substrate, so that it has excellent optical transparency and has a tin surface. Since an electromagnetic wave shielding mesh is formed, and an antireflection layer (AR) and a near infrared (NIR) blocking and color correction layer are formed only on the opposite side of the printing surface, moisture resistance can be obtained. Is simplified. Further, the yellowing phenomenon occurs due to the reaction between the conductive metal contained in the electromagnetic wave shielding member, which is the printed layer, and the tin surface. I found that it showed an improvement. In other words, the yellowing phenomenon has been regarded as a problem in the past, but the present invention appropriately reduces the reflection of external light compared to the air surface by appropriately using the yellowing phenomenon that occurs relatively larger than the air surface. In addition, since the blackness can be improved, it was confirmed that the optical characteristics are advantageous. Therefore, when the electromagnetic wave shielding filter of the present invention is applied to a panel, the printed layer faces the panel portion, and the glass layer and the optical functional layer are exposed to the outside.

  Therefore, the electromagnetic wave shielding filter formed by printing on a specific tempered glass substrate using the black conductive paste composition of the present invention and then firing includes a mesh pattern having a constant form, thickness, and line width. By simplifying the process and significantly improving the optical characteristics of the plasma display, it is possible to improve the quality and the continuous process.

  Such an electromagnetic wave shielding filter according to the present invention includes: i) an air having a relatively small amount of tin distribution on one surface and a relatively small amount of tin distribution on the other surface compared to the tin surface. A transparent tempered glass substrate having a surface; and ii) an electromagnetic wave shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate. The electromagnetic wave shielding member is applied to shield electromagnetic waves.

  The transparent tempered glass substrate may further include a color correction layer and a near-infrared blocking layer, and an antireflection layer, which are sequentially formed under the air surface. Accordingly, the antireflection layer is exposed to the outside air.

  Further, the color correction and near-infrared blocking layer and the antireflection layer may be formed on both sides of the film in the form including a film such as PET under the air surface of the transparent tempered glass substrate. At this time, the antireflection layer is preferably located at the lowermost part of the glass substrate. For example, the transparent tempered glass substrate may include a near-infrared blocking layer, a PET film, and a color correction layer under the air surface of the transparent tempered glass substrate. The film having the structure can be laminated using an adhesive or the like below the air surface of the transparent tempered glass substrate. In another method, for example, according to the present invention, a near-infrared blocking layer, a PET film, a color correction layer, and an antireflection layer can be sequentially formed 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 antireflection layer may be formed in one or less on one surface of the film in a form including a film such as PET under the air surface of the transparent tempered glass substrate. Thereafter, the formed two films are laminated and used. At this time, it is desirable that the antireflection layer is located at the lowermost part 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, and a near-infrared shielding layer is formed on the upper part of the PET film, and then the two films are laminated and used. Accordingly, the structure includes a PET film, a color correction layer, a PET film, and a near-infrared shielding layer below the air surface of the transparent tempered glass substrate, and an antireflection layer can be located thereunder. Alternatively, the order of laminating the two layers is reversed, and the lower surface of the air surface of the transparent tempered glass substrate includes a PET film, a near-infrared shielding layer, a PET film, and a color correction layer, and an antireflection layer is positioned therebelow. it can. Here, in the two films, the remaining surface of the PET film may include the entire glass substrate, or any one of the glass substrates. The film having the structure can be laminated using an adhesive or the like below the air surface of the transparent tempered glass substrate. In another method, for example, the method of the present invention can sequentially form each layer using a method such as coating on the lower portion of the glass substrate.

  The color correction and near-infrared blocking layer may include a near-infrared shielding dye having a near-infrared absorbing function having a wavelength of 850 to 1250 nm and a selective light-absorbing material for neon wavelength blocking and color correction. The near-infrared shielding dye may include, for example, a material selected from the group consisting of nickel complex-based, phthalocyanine-based, cyanine-based, diimonium-based compounds, and mixtures thereof. The selective light-absorbing substance for blocking the neon wavelength and correcting the color includes at least one substance selected from the group consisting of azo, styryl, cyanine, anthraquinone and tetraazapopyrin compounds. Can do. The near-infrared blocking layer and the color correction layer are manufactured by mixing the above-described near-infrared absorbing material and a selective light-absorbing material in a polymer resin and a solvent, and coating on a transparent substrate such as a glass substrate having a film underneath. can do.

  The antireflection layer may include a low refractive layer including a low refractive index material and a high refractive layer including a high refractive index material. The low refractive index single layer is easy to manufacture, but the antireflection performance can be lowered as compared with the multilayer stack. The low refractive index material may include one or more materials selected from the group consisting of fluorine-based materials, silicon oxide, magnesium fluoride, aluminum oxide, and the like. Examples of the high refractive index substance include one or more substances 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. Can be included. The antireflection layer is formed by forming a hard coating layer on a substrate and alternately coating a coating solution containing a high refractive index material and a coating solution containing a low refractive index material on the hard coating layer. be able to.

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

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

  In the black conductive paste composition, MA (methyl acrylate, methyl acrylate), BM (butyl methacrylate, butyl methacrylate), HEMA (hydroxyethyl methacrylate), MMA (methyl methacrylate, methyl methacrylate) are used as the acrylate polymer resin. Any one polymer selected from the group consisting of ethyl acrylate (EA), ethylhexyl acrylate, nonyl acrylate and methacrylates, or a copolymer of two or more thereof. It is done. Preferably, as the acrylate polymer resin, MA (methyl acrylate, methyl acrylate), BM (butyl methacrylate, butyl methacrylate), HEMA (hydroxyethyl methacrylate, hydroxyl methacrylate), and MMA (methyl methacrylate, methyl methacrylate) are used. 30]: [30 to 60]: [10 to 20]: [10 to 20] A copolymer copolymerized in a weight ratio is used. However, the acrylate polymer resin is not limited to this, and any other acrylate polymer resin known to be usable as a binder resin in the conductive paste composition for electromagnetic wave shielding filters is specially used. It can be used without any restrictions.

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

  The acrylate polymer resin preferably 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 the flow characteristics of the polymer are increased, so that the printing process of the black conductive paste composition (for example, In the case of the gravure offset printing step), it is difficult to transmit the pattern from the gravure groove to the blanket, and when it exceeds 100,000, it becomes difficult to put the composition into the gravure groove due to excessive elastic properties of the polymer.

  The monomer or oligomer preferably contains one or more selected from the group consisting of acrylate compounds, alkoxylate compounds, dimethyl sulfoxide, and unsaturated polyester compounds.

  Examples of the monomer or oligomer include methyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, glycidyl methacrylate, butyl methacrylate, ethyl methacrylate, benzyl methacrylate, ethyl triglycol 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, Silicon acrylate, Trimethylolpropane triacrylate, Neopentyl glycol hydroxypiva -Modified caprolactone (Neopentylglycolate diacrylate modified caprolactone), polyethylene glycol diacrylate, polypropylene glycol diacrylate, tetraethylene glycol diacrylate, pentaerythritol triacrylate triacrylate triacrylate ethylene trioxide triacrylate ethylene trioxide triacrylate ethylene trioxide triacrylate ethylene trioxide triacrylate Methylolpropane triacrylate modified polypropylene oxide (modified PO), dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate Dipentaerythritol hexaacrylate, modified caprolactone, ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, pentaerythritol ethoxylated triacrylate, methacrylate triacrylate, methacrylate triacrylate , Polyester methacrylate compounds, silicon methacrylate, trimethylolpropane trimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tetraethyleneglycol Dimethacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol pentamethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol tetramethacrylate, pentaerythritol ethoxylated trimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, Bisphenol A ethoxylated dimethacrylate (Bisphenol A Dimethacrylate), trimethylolpropane ethoxylate (4/15 EO / OH), trimethylolpropane ethoxylate (20/3 EO / OH), trimethylolpropane propoxylate (1 PO / H), including one or more selected from the group consisting of dimethyl sulfoxide and unsaturated polyesters. At this time, the dimethyl sulfoxide is generally used as a solvent, but in the present invention, it can be used as a substitute for a monomer. More preferably, the monomer or oligomer may be selected from the group consisting of urethane acrylate, trimethylolpropane triacrylate modified ethylene oxide, trimethylolpropane triacrylate modified propylene oxide and bisphenol A ethoxylated dimethacrylate. .

  In addition, the monomer or oligomer is not particularly limited to the above-described example, and can be dried by an offset method, can improve the transferability of the paste, and can be any arbitrary usable for the conductive paste composition for electromagnetic wave shielding filters. Monomers and oligomers can also be used.

  The content of the monomer or oligomer is preferably 10 to 90 parts by weight with respect to the total amount 100 of the acrylate polymer resin and the monomer or oligomer. Accordingly, the weight ratio of the acrylate polymer resin to the monomer or oligomer can be 10:90 to 90:10. At this time, if the content of the monomer or oligomer is less than 10 parts by weight, there is a problem that the drying prevention effect is reduced and the drying rate of the paste composition is increased, and if it exceeds 90 parts by weight, the elasticity of the paste composition is increased. In some cases, the pattern spreading phenomenon becomes serious and the printability deteriorates, so that it does not have its own shape.

  The content of the acrylate polymer resin and the monomer or oligomer is preferably 5 to 15 parts by weight in the entire paste composition. If the content of the acrylate polymer resin and the monomer or oligomer is less than 5 parts by weight, problems may occur during the printing process due to a decrease in elasticity of the paste composition. There may be a problem that the electric resistance of the formed pattern increases.

  On the other hand, in the black conductive paste composition, the solvent is a medium for dissolving other components, and is preferably contained in 5 to 15 parts by weight in the entire paste composition. If the content of the solvent is less than 5 parts by weight, there is a problem that the drying speed of the paste composition is increased and it is difficult to proceed with continuous printing. If the content exceeds 15 parts by weight, the viscosity of the paste composition is lowered. There is a problem that printability deteriorates.

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

  By including both the high boiling point solvent and the low boiling point solvent, it is possible to maintain the viscosity and fluidity of the paste composition at a desired level, and thereby the paste composition in the step of printing the paste composition on a glass substrate. In addition to facilitating the transition of the composition to the pattern, the pattern spreading phenomenon is suppressed and the straightness of the pattern can be further improved.

  As the high-boiling 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 having the above boiling point and known to be usable for the conductive paste composition for electromagnetic wave shielding filters can be used.

  Examples of the low boiling point solvent include propylene glycol monomethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether propionate, ethyl ether propionate, propylene glycol monomethyl ether acetate. One or more solvents selected from the group consisting of methyl ethyl ketone and ethyl lactate can be used, and other solvents having a boiling point of less than 200 ° C. can be used for the conductive paste composition for electromagnetic wave shielding filters. Any given organic solvent can be used.

  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. In the unlikely event that the high-boiling solvent is contained in the solvent in an amount of less than 12% by weight, the content of the low-boiling solvent is excessively increased, and the fluidity reduction rate of the paste composition is excessively increased. The transition to may not be easy. On the other hand, if the content of the high boiling point solvent is excessively increased beyond 88% by weight, the fluidity of the paste composition becomes difficult to suppress, and the pattern spreading phenomenon becomes serious. Through the printing of the paste composition The straightness of the formed pattern can be reduced.

On the other hand, in the black conductive paste composition of the present invention, as the glass powder, Pb-based and Pb-free-based powders can be used. It is desirable to consider the improvement of the organic material removal temperature and the pattern adhesion to the glass substrate using a free powder. Examples of such Pb-free powder include Bi glass powder such as Bi ₂ O ₃ glass powder. Moreover, during the production of glass powder, or glass powder black or colored pigment colored prepared by mixing, can likewise be desirable use a glass powder containing colored components such as V ₂ O _5.

  The content of the glass powder can be 1 to 10 parts by weight, preferably 2 to 7 parts by weight in the whole paste composition. When the content of the glass powder is less than 1 part by weight, there is a problem that the adhesive force of the paste composition to the glass substrate is weakened. When the content exceeds 10 parts by weight, the electric resistance of the pattern formed by the paste composition is high. Thus, there is a problem that the electromagnetic wave shielding efficiency is lowered.

Further, in the black conductive paste composition, a metal powder for electrodes is used as the conductive metal. More specifically, silver, copper, nickel, tin, or an alloy thereof is used alone or in combination. Can be used.
The content of the conductive metal is preferably 50 to 90 parts by weight in the entire paste composition. If the content of the conductive metal exceeds 90 parts by weight, the viscosity of the paste composition increases and dispersion becomes difficult and the printing characteristics decrease, and if it is less than 50 parts by weight, the pattern formed with the paste composition The electromagnetic shielding performance required for an electromagnetic wave shielding filter for a display device may deteriorate due to an increase in electrical resistance.

  The metal powder used as the conductive metal may preferably have an average particle size of 0.3 to 30 μm, more preferably 0.5 to 10 μm, and most preferably 0.5. It can have an average particle size of ˜5 μm. In the unlikely event that the metal powder has an average particle size that is too small, less than 0.3 μm, it becomes difficult to disperse, and the paste composition may have a high viscosity or gel, so that the printing characteristics are reduced, It is difficult to form a good pattern through printing of the paste composition. 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, and thereby the electromagnetic wave shielding filter is uniform. Therefore, it is difficult to form a desirable pattern and an electromagnetic wave shielding filter by generating holes in the pattern. In contrast, if the metal powder has an average particle size of 0.3-30 μm, more preferably an average particle size of 0.5-10 μm, most preferably an average particle size of 0.5-5 μm, Printing properties and electromagnetic wave shielding performance of the paste composition can be further improved, and generation of holes in the pattern may be prevented.

  On the other hand, in the black conductive paste composition, the black pigment is used for reducing external light reflection and improving contrast of a display device, and includes cobalt, copper, ruthenium, manganese, nickel, chromium, or iron. A compound of a system can be included, and preferably a compound of a cobalt system can be included. Further, the black pigment is more preferably used in a form in which auxiliary pigments such as copper, ruthenium, manganese, nickel, chromium or iron are mixed to improve the blackness in addition to the cobalt compound.

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

  The black conductive paste composition may further include a dispersant as necessary. As the dispersant, a polymer that is widely known in the art or commercially available can be used without any particular limitation. The dispersant content is preferably 0.05 to 1.0 parts by weight in the entire paste composition. When the content of the dispersant is less than 0.05 parts by weight, sufficient dispersibility and contrast cannot be expected, and when it exceeds 1.0 parts by weight, the electrical resistance increases and the electromagnetic wave shielding characteristics deteriorate. There is.

  The electromagnetic wave shielding member may include i) one or more first shielding parts extending in one direction, and ii) one or more second shielding parts intersecting the first shielding part. At this time, the width of the first shielding part may be greater than 0 and 50 μm or less, and preferably 15 to 30 μm. The one or more first shielding parts may include a plurality of first shielding parts, and an average pitch of the plurality of first shielding parts may be greater than 0 and not more than 500 μm. Preferably, an average pitch of the plurality of first shielding portions may be 200 μm to 400 μm.

  Also, the angle formed by the intersection of the first shielding part and the second shielding part may be 60 ° to 120 °, and preferably 80 ° to 100 °. Most preferably, the angle formed by the intersection of the first shielding part and the second shielding part may be substantially 90 °.

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

  The electromagnetic wave shielding member may have a polygonal opening, and the opening may be chamfered. The lengths of all sides forming the polygon can be substantially the same, and further, the polygon can be a substantially square.

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

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

Meanwhile, the present invention provides a display device formed using the paste composition described above.
Such a display device includes i) the transparent tempered glass substrate, ii) an electromagnetic wave shielding member formed in a mesh shape on the tin surface of the transparent tempered glass substrate, and iii) a display that displays the image and faces the glass substrate. Includes panels. At this time, the electromagnetic wave 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 positioned between the first substrate and the second substrate. At this time, the electromagnetic wave shielding member can cross the black layer. The electromagnetic wave shielding member may be in contact with 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. Further, the electromagnetic wave shielding member can have a polygonal opening, and the opening can be chamfered. The lengths of all sides forming the polygon can be substantially the same, and further, the polygon can be a substantially square.

  The electromagnetic wave shielding member can be formed by subjecting the paste composition to offset printing (particularly gravure offset printing) and firing on the tin surface of a transparent tempered glass substrate. The electromagnetic wave shielding member may include i) one or more first shielding parts extending in one direction, and ii) one or more second shielding parts intersecting the first shielding part. At this time, the width of the first shielding part may be larger than 0 and 50 μm or less, and preferably 15 μm to 30 μm. The one or more first shielding parts may include a plurality of first shielding parts, and an average pitch of the plurality of first shielding parts may be greater than 0 and 500 μm or less. Preferably, the average pitch of the plurality of first shielding portions is 200 μm to 400 μm.

  The angle formed while the first shielding part and the second shielding part intersect may be 60 ° to 120 °, and preferably 80 ° to 100 °. Most preferably, the angle formed while the first shielding portion and the second shielding portion intersect is substantially 90 °.

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

  The display panel may be a plasma display panel.

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

  Therefore, the present invention can provide an electromagnetic wave shielding filter having a uniform mesh pattern shape, line width and thickness and excellent quality. Such an electromagnetic wave shielding filter can be applied to a display device to further improve the external characteristics.

  In addition, the present invention can manufacture an electromagnetic wave shielding filter in a continuous process using an offset printing method that is simpler and less expensive than other processes.

  Moreover, when manufacturing the display apparatus provided with the electromagnetic wave shielding filter having excellent outer shape quality described above, the electromagnetic wave shielding effect of the display apparatus can be maximized.

It is a schematic process drawing of the manufacturing process of the conventional electromagnetic wave shielding filter. It is an electron micrograph which shows the Cu mesh pattern formed by the method of FIG. 1 is a schematic perspective view of an electromagnetic wave shielding filter according to an embodiment of the present invention. It is the fragmentary sectional view cut | disconnected along the II-II line | wire of FIG. FIG. 3 is a schematic diagram showing a method for manufacturing the electromagnetic wave shielding filter of FIG. 2. It is sectional drawing which shows the block diagram of the electromagnetic wave shielding filter by this invention manufactured by the said method. It is an electron micrograph which shows the mesh pattern of the electromagnetic wave shielding filter by this invention. FIG. 3 is a schematic perspective view of a display device including the electromagnetic wave shielding filter of FIG. 2. It is the fragmentary sectional view cut | disconnected along the VV line | wire of FIG.

  Hereinafter, with reference to the accompanying drawings, the electromagnetic wave shielding filter and the display device will be described so that those skilled in the art to which the present invention pertains can easily carry out. In order that those having ordinary skill in the art to which the present invention pertains will be easily understood, the embodiments described below are merely illustrative of the present invention, and various modifications can be made without departing from the concept and scope of the present invention. Can be changed in form. Wherever possible, the same or similar parts will be given the same reference numerals.

  All terms, including technical and scientific terms used below, have the same meaning as commonly understood by those with ordinary skill in the art to which this invention belongs. Terms defined in the dictionary shall be further interpreted as having a meaning consistent with the relevant technical literature and the presently disclosed content, and shall be interpreted in an ideal or very formal sense unless otherwise defined. There is no.

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

  FIG. 2 schematically shows an electromagnetic wave shielding filter 100 according to an embodiment of the present invention. The enlarged circle in FIG. 2 shows the inside of the electromagnetic wave shielding filter 100 in an enlarged manner.

  As shown in FIG. 2, the electromagnetic wave shielding filter 100 is provided with an antireflection layer 60 as an optical functional layer at the top, and the color correction and near infrared ray shielding layer 50 is an air surface (Air surface) of the transparent tempered glass substrate 20. And the optical functional layer is exposed to the outside air. Moreover, although not shown in figure, the upper part of the transparent tempered glass substrate 20 which has a color correction and near-infrared shielding layer and an antireflection layer in the lower part contains a tin surface (tin surface). Moreover, the electromagnetic wave shielding member 10, the edge layer 30, and the grounding member 40 are included on the tin surface, and are directed to the panel portion. The present invention uses the above-described transparent tempered glass substrate 20 in order to form the electromagnetic wave shielding member 10 by an offset printing (particularly, gravure offset printing) method. The long side of the transparent tempered glass substrate 20 is aligned with the x axis, and the short side is aligned with the y axis.

  The electromagnetic wave shielding member 10 is connected to the ground member 40 and grounded. Accordingly, the electromagnetic shielding member 10 can absorb and remove electromagnetic waves. As a result, the electromagnetic wave shielding member 10 functions as a filter that shields electromagnetic waves. The edge layer 30 is formed along the periphery of the transparent tempered glass substrate 20, and the ground members 40 are positioned at both ends of the transparent tempered glass substrate 20 in the x-axis direction in order to ground the electromagnetic wave shielding member 10. In addition, the color correction and near-infrared shielding layer 50 and the optical function layer of the antireflection layer 60 are sequentially formed on the opposite surface of the transparent tempered glass substrate on which the electromagnetic wave shielding member 10 that is the printing layer is formed.

  As shown in the enlarged circle of FIG. 2, the electromagnetic wave 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 wave shielding member 10 is formed in a mesh shape so that an image emitted from the display device is displayed outside. Since the electromagnetic wave shielding member 10 has the opening 109, the electromagnetic wave can be blocked while allowing an image to pass through the opening 109.

  The electromagnetic shielding member 10 includes a first shielding part 101 and a second shielding part 103. The first shielding part 101 extends in the x-axis direction and intersects the second shielding part 103. That is, as shown in the enlarged circle of FIG. 1, the first shielding part 101 and the second shielding part 103 meet each other to form an angle α1. The angle α1 can be between 60 ° and 120 °. When the angle α1 is too large or too small, the distance between the first shielding part 101 and the second shielding part 103 becomes too close, and the aperture ratio may become too small. More preferably, the angle α1 can be between 80 ° and 100 °. In this case, the distance between the 1st shielding part 101 and the 2nd shielding part 103 can be maintained appropriately. It is most desirable if the angle α1 is substantially 90 °.

  A method for manufacturing an electromagnetic wave shielding filter includes: i) providing a gravure roll having a mesh-shaped groove; ii) filling the groove with a black conductive paste composition; and iii) the gravure. Providing a blanket roll facing the roll and rotating in a direction opposite to the rotation direction of the gravure roll; iv) transferring the conductive paste composition to the blanket roll while rotating the gravure roll V) providing 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 onto the transparent tempered glass substrate; And vii) firing the conductive paste composition to produce the transparent strong A step of forming a shielding member composed of a single layer for shielding electromagnetic waves on the tin surface of the vitrified glass substrate may be included.

  At this time, the substrate is washed with water through a normal washing device before printing.

  The transparent tempered glass substrate is manufactured by strengthening the plate glass manufactured by the float method as described above. In the present invention, the transparent tempered glass substrate is divided into a tin surface (tin surface) and an air surface (Air surface). Print.

  In the embodiment of the present invention, a gravure roll 55 (shown in FIG. 4) in which mesh-shaped grooves 551 (shown in FIG. 4) are formed in the oblique direction is used to form the mesh-shaped electromagnetic shielding member 10. If the groove 551 is not formed in the oblique direction and is orthogonal to the rotation direction of the gravure roll 55, the paste composition 10 a (illustrated in FIG. 4) that is the raw material of the electromagnetic wave shielding member 10 accommodated in the groove 551 is removed from the groove 551. Not well away. That is, since the paste composition 10a is not well influenced 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 coincides with the direction in which the groove 551 is extended, the paste composition 10 a can be well separated from the groove 551 by the rotation 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 wave shielding member 10 having the opening 109 having a uniform size can be formed.

  More specifically, when a groove is formed only in a direction that coincides with the rotation direction of the gravure roll, it is impossible to form a mesh-shaped shielding member. That is, although the mesh form can have a rectangular shape, grooves must be formed also in the direction orthogonal to the rotation direction of the gravure roll, so that it is difficult to transfer the paste composition to the blanket roll.

  As shown in the enlarged circle of FIG. 2, when the electromagnetic wave shielding member 10 is formed on the tin surface of the transparent tempered glass substrate 20 using the method described above, the first shielding portion 101 has a constant angle α2 with respect to the x-axis direction. Form. Here, the angle α2 is an angle formed between a tangent formed by the gravure roll and the blanket roll and the first groove portion, and may be 20 ° to 70 °. When the angle α2 is too small or too large, the first shielding part 101 and the second shielding part 103 are densely packed, and the electromagnetic wave shielding effect may be lowered. Further, when the electromagnetic wave shielding filter 100 is used in the display device 200 (illustrated in FIG. 7), a moire shape can be generated while overlapping with the black layer 651 of the display device 200. More specifically, the angle α2 may be 35 ° to 55 °.

  As shown in the enlarged circle of FIG. 2, the resolution of the image can be increased by forming the width W of the electromagnetic wave shielding member 10 to be small and maximizing the area of the opening 109. For this reason, the width W of the electromagnetic wave shielding member 10 can be greater than 0 and 50 μm or less. In this case, the electromagnetic wave shielding member 10 cannot be observed with 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 becomes low. More specifically, the width W of the electromagnetic wave 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 made larger than 0 and 500 μm or less. When the average pitch P of the electromagnetic wave shielding member 10 is too large, the electromagnetic wave shielding member 10 is not formed densely, so that the electromagnetic wave may not be absorbed and may be emitted to the outside. As a result, the electromagnetic shielding effect is reduced. More specifically, the average pitch P of the shielding members 10 is preferably 200 μm to 400 μm.

  The electromagnetic wave shielding member 10 may include a conductive metal in order to maximize the electromagnetic wave shielding effect. Since the conductive metal can collect the electromagnetic wave passing through the electromagnetic wave shielding filter 100, the electromagnetic wave shielding effect is excellent. As the conductive metal, silver, copper, nickel, tin, or an alloy thereof is used. Since such a conductive metal has excellent electrical conductivity, it can efficiently shield electromagnetic waves.

  FIG. 3 partially shows a cross-sectional structure of the electromagnetic wave shielding filter 100 cut along the line II-II in FIG.

  As shown in FIG. 3, the electromagnetic wave shielding member 10 has a tin surface (tin surface) 23 on the upper portion of the transparent tempered glass substrate 20, an air surface (air surface) 25 on the lower portion, and an upper portion of the tin surface 23. And it forms on the edge layer 30 formed in the periphery of the said tin surface upper part. Since the edge layer 30 includes black ceramic, the outer shape of the electromagnetic wave shielding filter 100 can be improved. Further, the edge layer 30 can efficiently connect the ground member 40 to the electromagnetic wave shielding member 10. The thickness of the edge layer 30 can be about 15 μm to 20 μm. After the grounding member 40 is formed on the tin layer 23 of the transparent tempered glass substrate 20 and the edge layer 30 formed on the tin surface 23 by printing the paste composition by an offset method, the electromagnetic wave shielding member 10 is formed. The grounding member 40 is formed thereon. A conductive film tape is used as the ground member 40. Thereafter, a color correction and near-infrared blocking layer 50 and an antireflection layer 60 are formed below the air surface 25.

  FIG. 4 schematically shows a process of manufacturing the electromagnetic wave shielding filter 100 of FIG. The electromagnetic wave shielding filter 100 can 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 10 a is pulled away from the gravure roll 55. In the setting step, the separated paste composition 10 a is applied onto the substrate 20. The dispenser 51 discharges the paste composition 10a at a preset time interval. The paste composition 10 a discharged from the dispenser 51 is accommodated in a groove 551 formed in the gravure roll 55. As already described above, the paste composition 10a can include an organic material having elasticity, a conductive metal, a solvent, a binder, a predetermined dispersant, and the like. The solvent can be used together with 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., and a glass powder, that is, a glass frit is used as the binder. As an organic substance, a normal acrylate resin, polyester, polyurethane, an oligomer, a monomer, etc. can be included. The solvent and the organic substance can be removed in the step of baking the substrate 20. The paste composition 10a further includes a black pigment and a predetermined dispersant.

  Since the amount of the paste composition 10a stored in the groove 551 is large, the paste composition 50a can 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 direction of the arrow (counterclockwise). 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 is appropriately filled while preventing overflow of the groove 551 of the gravure roll 55.

  The blanket roll 57 is positioned to face the gravure roll 55. The blanket roll 57 rotates in a direction (clockwise) opposite to the rotation direction of the gravure roll 55. As a result, the paste composition 10 a accommodated in the groove 551 is transferred onto the blanket roll 57 while the gravure roll 55 is associated with the blanket roll 57. Therefore, the paste composition 10 a 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 prepared by being cleaned. Thus, a mesh-form paste composition 10a for forming the electromagnetic wave 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 strengthening a plate glass produced by a float method, and in the present invention, the paste composition is printed on the tin surface by dividing the tin surface and the air surface. In the drawings, the tin surface on the glass substrate 20 is not shown for convenience. Through such printing, the printed layer of the final filter product is exposed to the outside air, and the printed layer is directed to the panel portion of the display element.

  Next, the substrate 20 is placed in a heating furnace (not shown) and heated to remove the solvent and organic matter contained in the paste composition 10a. The paste composition 10a can be dried before such a firing step. Moreover, the electromagnetic wave shielding member can be directly formed by heating the transparent tempered glass substrate 20 to remove the solvent and organic matter. That is, an electromagnetic wave shielding filter is immediately manufactured without performing a separate process such as etching the paste composition 10a. Therefore, since the process of the present invention is simple, the manufacturing cost of the electromagnetic wave shielding filter can be reduced.

  In the baking process, the temperature is preferably 500 to 540 ° C. During the baking, the substrate is held at the temperature for 10 to 30 minutes and then gradually cooled. At this time, the higher the firing temperature, the greater the tempering annealing of the tempered glass substrate and the lower the impact resistance. Therefore, the lower the firing, the more advantageous. In addition, as the firing temperature increases, the conductive metal particles in the electromagnetic wave shielding member react with the tin layer to increase the degree of migration, and yellowishness increases. In other words, if the firing temperature is very high, the degree of yellowing becomes severe, and it becomes difficult to correct the color when producing filters. It is necessary to lower the range. Therefore, according to the present invention, the resistance value and the optical characteristics can be appropriately adjusted by adjusting the firing temperature to the appropriate range as described above during printing of the tin surface.

  Since the other contents of the offset printing method in the present invention can be easily understood by those having ordinary knowledge in the technical field to which the present invention belongs, the detailed description thereof will be omitted.

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

  In addition, the present invention forms a color correction and near-infrared blocking layer 50 and an antireflection layer 60 on the opposite side of the printed layer for the role of an electromagnetic wave filter. At this time, the forming method is performed by a normal method. Therefore, detailed description thereof is omitted.

  FIG. 5 is a cross-sectional view illustrating a configuration diagram of an electromagnetic wave shielding filter according to the present invention manufactured by the above method. FIG. 6 is an electron micrograph showing a mesh pattern of the electromagnetic wave 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 a paste composition 10 a is formed on the tin surface 23. A color correction and near-infrared blocking layer 50 and an antireflection layer 60, which are optical functional layers, are formed under the glass substrate 20 to protect the air surface 25 and function as a filter. In the present invention, since a glass substrate printed on a tin surface is immediately provided, a structure in which a PET film and an adhesive layer are excluded unlike a conventional film mesh such as a Cu mesh when compared with the optical functional layer and the like. Is made possible to improve the optical properties (transparency) and simplify the structure, thereby simplifying the process. In addition, when the printing filter of the present invention is applied to a panel, the printing layer faces the panel portion, and the film layers 50 and 60 are exposed to the outside.

  On the other hand, when an electromagnetic wave shielding filter is manufactured 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 photolithography method and the plating method described above cannot form a pattern directly on the substrate. For example, the plating method is performed by winding a base material in a roll form and immersing it in a plating bath. However, since the substrate cannot be wound in a roll form, it is impossible to form an electromagnetic wave shielding member by plating the substrate. is there. Further, when a substrate is used, the process is complicated because the pattern must be bonded to the substrate. The offset printing method can solve the above-mentioned problems. That is, in the offset printing method, since the electromagnetic wave shielding member 10 is formed immediately on the tin surface of the transparent tempered glass substrate 20, the process can be simplified and the manufacturing cost can be reduced. In addition, the offset printing method does not discharge harmful substances, so it does not cause pollution.

  FIG. 7 schematically shows a display device 200 including the electromagnetic wave shielding filter 100 of FIG. The enlarged circle in FIG. 7 shows the display device 200 as viewed from the z-axis direction.

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

  As shown in the enlarged circle of FIG. 7, the electromagnetic wave shielding member 10 is located on the black layer 651 included in the display panel 600 (shown in FIG. 8). 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 circle of FIG. 7, a second substrate 620 (shown in FIG. 8) is located between the electromagnetic wave shielding member 10 and the black layer 651, and a glass member is placed on the electromagnetic wave shielding member 10. 20 (shown in FIG. 8) is located.

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

  As shown in the enlarged circle of FIG. 7, the electromagnetic wave shielding member 10 has a diamond-shaped opening 109. Although not shown in FIG. 7, it is preferable that the electromagnetic wave shielding member 10 is substantially a regular square. In this case, the electromagnetic shielding effect can 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 wave 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 diamond shape in the enlarged circle of FIG. 7, this is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, the opening 109 can be polygonal.

  The electromagnetic shielding member 10 is formed by an offset printing method using shielding portions that intersect each other. Therefore, the width of the electromagnetic wave shielding member 10 is slightly increased at the intersection where the plurality of shielding portions meet each other. As a result, the opening 109 has a chamfered shape. That is, since the width of the electromagnetic wave shielding member 10 is slightly increased at the intersection of the electromagnetic wave shielding member 10, the opening 109 has a shape with no corners. Since the electromagnetic wave shielding member 10 is continuously formed without being cut by such a shape of the opening 109, the electromagnetic wave can be shielded over the entire surface of the electromagnetic wave shielding member 10.

  As shown in the enlarged circle of FIG. 7, the electromagnetic wave shielding member 10 is formed while three-dimensionally intersecting with the black layer 651. Therefore, the phenomenon that the image becomes cloudy can be prevented. Furthermore, since the electromagnetic wave shielding member 10 has such a fine width that it is difficult to recognize with the naked eye, it hardly affects the image quality. Therefore, as shown in the enlarged circle of FIG. 7, even when the electromagnetic wave shielding member 10 is positioned on the black layer 651, an image having a high resolution can be displayed.

  FIG. 8 partially shows a cross section taken along line VV in FIG.

  FIG. 8 shows a plasma display panel as the display panel 600. The plasma display panel shown in FIG. 8 is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, other display panels that require an electromagnetic wave shielding filter are also 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, a protective film 635 and a black layer 651. The inside of the display panel 600 is filled with a discharge gas. The first substrate 610 and the second substrate 620 face each other. The barrier rib 660 forms a large number of discharge cells, and a phosphor layer is formed inside the discharge cells. The dielectric layer 630 protects the address electrode 640 and the display electrode 680 from electrons. The protective film 635 protects the dielectric layer 630 located above.

  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. The ultraviolet rays generated by the discharge collide with the phosphor layer 670, and visible light is emitted from the phosphor layer 670. On the other hand, a black layer 651 is formed on the partition 660 in order to improve the contrast ratio. The black layer 651 is located between the first substrate 610 and the second substrate 620. Since the black layer 651 is formed on the partition wall 660 that does not emit light, loss of light emitted from the phosphor layer 670 can be reduced. More specifically, as shown in FIG. 8, the black layer 651 is formed so as to be in contact with the partition 660, or as another example, formed on the dielectric layer 630 on the partition 660. You can also.

  As shown in FIG. 8, the electromagnetic wave shielding filter 100 is positioned on the display panel 600. Therefore, the electromagnetic wave shielding filter 100 can shield electromagnetic waves emitted from the display panel 600. Since the electromagnetic wave shielding member 10 faces the second substrate 620, it is not exposed to the outside. Therefore, it is possible to prevent the electromagnetic wave shielding member 10 from being damaged, and it is possible to prevent a decrease in the outer shape due to the electromagnetic wave shielding member 10. Further, only the optical functional layer including the color correction and near infrared ray blocking layer 50 and the antireflection layer 60 is exposed to the outside.

  On the other hand, when the first substrate 610 and the second substrate 620 are thin, the display panel 600 is vulnerable 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 is thick and very resistant to external impact. For example, the durability of the display device 200 can be improved by the electromagnetic wave shielding filter 100 by forming the thickness t20 of the substrate 20 to be greater than the thickness t620 of the second substrate 620.

  Hereinafter, the present invention will be described in more detail through experimental examples. Such experimental examples are merely to illustrate the present invention, and the present invention is not limited thereto.

  Production example

  For the gravure offset printing as desired, stir the solvent, glass powder, conductive metal, black pigment and dispersant into the acrylate polymer resin at room temperature with the following composition and content, and finally use a 3-roll mill. A black conductive paste composition was produced.

  66.7% by weight of acrylate polymer resin and monomer mixed at a weight ratio of 66.7: 33.3, 7% by weight of butyl carbitol acetate (BCA), 2.2% by weight of diethylene glycol methyl ethyl ether, dispersant A black conductive paste containing 0.3 wt%, conductive metal 75 wt%, black powder 5.5 wt% and glass powder 4 wt% was produced.

  Here, the acrylate polymer resin has a weight average molecular weight of 15,000, and includes MA (methyl acrylate, methyl acrylate), BM (butyl methacrylate, butyl methacrylate), HEMA (hydroxyethyl methacrylate, hydroxyethyl methacrylate), and MMA (methyl methacrylate), methyl. Methacrylate) are copolymerized at a weight ratio of 30: 40: 10: 20, respectively.

  The monomer is trimethylolpropane triacrylate modified ethylene oxide.

Moreover, the block copolymer containing a basic pigment affinity group is DISPERBYK-2050 manufactured by BYK. The conductive metal is a spherical silver powder, and the average particle size is 1.5 μm. The black pigment is Co. Bi ₂ O ₃ glass powder was used as the glass powder.

Example (formation of electromagnetic shielding filter)

  Using the paste composition produced in the production example, gravure offset printing was performed so as to meet the pattern standard used for the electromagnetic wave 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 the offset printing apparatus shown in FIG. At this time, the line width of the mesh pattern was 25 μm, and the pattern standard pitch was 270 μm.

  Next, the paste composition formed on the tin surface of the transparent tempered glass substrate in the firing step 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)

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

Experimental example (characteristic evaluation of electromagnetic shielding filter)

  The optical values such as blackness and yellowing of the electromagnetic wave shielding filters 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 corresponding to each substrate surface was performed on a total of 6 lots, and printing was averaged 30 times for each lot. Moreover, durability of the electromagnetic wave shielding mesh printed matter of an Example and a comparative example was evaluated, and the evaluation criteria are as follows.

(Optical property evaluation criteria)
Irradiate the D65 light source in contact with the opposite side of the printed surface of the transparent tempered glass substrate on which the electromagnetic wave shielding mesh is printed / fired under the white light source condition, and the blackness (L), yellowing (b), total reflection (SCI Y ), Diffuse reflection (SCE Y) values were measured at 3 points for each sample and averaged 30 per lot (6 lots in total). At this time, the equipment used for the measurement was a spectrocolorimeter (model name Minolta CM2600d).

(Moisture resistance evaluation standard)
A protective film was attached to the opposite surface of the formed mesh pattern substrate to be printed and allowed to stand under constant temperature and humidity conditions, and optical value change and external shape change were comparatively evaluated after removing the protective film.

That is, the sample of the example and the comparative example are allowed to stand under the following high temperature and high humidity conditions, and the change of the optical value and the change of the outer shape are compared and evaluated. Measure the transmission color coordinates and reflectance with changes in optical values with UN / VIS / NIR spectrometer (Spectrophotometer) (model name Hitachi U4100), and measure transmittance and haze with turbidity meter (model name Nippon Denshoku NDH). did.
* High temperature / high humidity condition: 60 ° C, 90% RH, 1000h
* Moisture resistance ○: External shape change X / Transparent color coordinate change ± 0.01 / Transmissivity change within 10%

  Through the results of Table 1, in the case of the example in which the paste composition is printed on the tin surface, compared to the comparative example in which the paste composition is printed on the air surface, the blackness value (L) is decreased and the reflection value (Y) is decreased. showed that. It has been confirmed that this has the effect of reducing the blackness and the reflection value by causing more yellowing of the glass substrate through tin printing and firing. Therefore, the method according to the present invention can be used to lower the optical value through tin surface printing by causing appropriate yellowing at an appropriate firing temperature. Further, it was confirmed that the white turbidity phenomenon occurred when printing on the air surface, but there was almost no change in the external characteristics and characteristic values when printing on the tin surface.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to these embodiments, and those skilled in the art are described in the above described scope and the following claims. It is understood that the present invention can be variously changed and modified without departing from the spirit and scope of the present invention.

Claims (34)

A transparent tempered glass substrate having a tin surface with a relatively large amount of tin distribution on one surface and an air surface with a relatively small amount of tin distribution compared to the tin surface on the other surface, and the transparent tempered glass substrate An electromagnetic wave shielding filter comprising an electromagnetic wave shielding member formed in a mesh shape on a tin surface of the ceramic. The transparent tempered glass substrate is produced by strengthening a plate glass produced by a float method.
The float method includes a step of manufacturing a plate glass in such a manner that a floated glass object floats on tin while allowing the molten glass object to flow over tin which is a molten metal. Item 2. The electromagnetic wave shielding filter according to Item 1. 2. The electromagnetic wave shielding filter according to claim 1, further comprising a color correction and near-infrared shielding layer formed in sequence below an air surface of the transparent tempered glass substrate; and an antireflection layer. 4. The electromagnetic wave according to claim 3, wherein the near-infrared blocking layer includes a near-infrared shielding dye having a near-infrared absorbing function having a wavelength of 850 to 1250 nm, and a selective light-absorbing material for blocking neon wavelengths and correcting colors. Shielding filter. The near-infrared shielding dye includes a material selected from the group consisting of nickel complex-based, phthalocyanine-based, cyanine-based, diimonium-based compounds, and mixtures thereof;
The selective light-absorbing material for blocking neon wavelength and color correction includes one or more materials selected from the group consisting of azo-based, styrylstyryl-based, cyanine-based, anthraquinone-based, and tetraazapopillin-based compounds. The electromagnetic wave shielding filter according to claim 4. The electromagnetic wave shielding filter according to claim 4, wherein the antireflection layer includes a low refractive layer including a low refractive index material and a high refractive layer including a high refractive index material. The low refractive index material includes one or more materials selected from the group consisting of fluorine compounds, silicon oxide, magnesium fluoride, and aluminum oxide,
The high refractive index substance includes 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 electromagnetic wave shielding filter according to claim 6. The electromagnetic wave shielding member is
One or more first shields extended in one direction;
The electromagnetic wave shielding filter according to claim 1, further comprising one or more second shielding parts intersecting with the first shielding part. The electromagnetic wave shielding filter according to claim 1, wherein the electromagnetic wave shielding member has a polygonal opening, and the opening is chamfered. The electromagnetic wave shielding filter according to claim 1, further comprising an edge layer formed along a periphery of the transparent tempered glass substrate, wherein the electromagnetic wave shielding member is formed on the edge layer. The filter for shielding electromagnetic waves according to claim 10, further comprising a grounding member connected to an end of the electromagnetic shielding member to ground the electromagnetic shielding member. 2. The electromagnetic wave shielding filter according to claim 1, wherein the electromagnetic wave 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 black conductive paste composition is
13. The electromagnetic wave shielding filter according to claim 12, comprising a) acrylate polymer resin and oligomer or monomer, b) solvent, d) glass powder, e) conductive metal, and f) black pigment. Acrylic 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 The electromagnetic wave shielding filter according to claim 12. The electromagnetic wave shielding filter according to claim 13, wherein the composition further comprises 0.05 to 1 part by weight of a dispersant. 14. The electromagnetic wave shielding filter according to claim 13, wherein the black pigment contains cobalt, copper, ruthenium, manganese, nickel, chromium, or an iron-based compound. The electromagnetic wave shielding filter according to claim 16, wherein the black pigment further includes an auxiliary pigment of copper, ruthenium, manganese, nickel, chromium, or iron. The electromagnetic shielding filter according to claim 13, wherein the acrylate polymer resin has a weight average molecular weight of 5,000 to 100,000. The electromagnetic wave shielding according to claim 13, wherein the solvent includes at least one high boiling solvent having a boiling point of 200 ° C. or higher and at least one low boiling solvent having a boiling point of less than 200 ° C. Filter. The glass powder is at least one selected from the group consisting of Pb-based powder, Pb-free powder, colored glass powder produced by mixing black or colored pigments, and glass powder containing a colored component of V ₂ O _5. The electromagnetic wave shielding filter according to claim 13, which is selected. 11. The electromagnetic wave shielding filter according to claim 10, wherein the conductive metal is an electrode metal powder selected from the group consisting of silver, copper, nickel, tin, and alloys thereof. Providing a gravure roll formed with mesh-shaped grooves;
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 rotation direction 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 an air surface on one side including a relatively large amount of tin distribution and a relatively small amount of tin distribution on the other side compared to the tin surface;
A step of applying the conductive paste composition onto a tin surface of the transparent tempered glass substrate while the blanket roll moves on the transparent tempered glass substrate; and baking the conductive paste composition to form the transparent tempered glass. The manufacturing method of the filter for electromagnetic wave shielding characterized by including the step of forming the shielding member which consists of a single layer which shields electromagnetic waves on the tin surface of a board | substrate. The method for manufacturing an electromagnetic wave shielding filter according to claim 22, wherein the transparent tempered glass substrate is manufactured by strengthening a plate glass manufactured by a float method. In the step of providing the gravure roll, the groove is
23. The method for manufacturing an electromagnetic wave shielding filter according to claim 22, further comprising at least one first groove portion extending in one direction and at least one second groove portion intersecting the first groove portion. 25. The electromagnetic wave shielding filter according to claim 24, wherein the one or more first groove portions include a plurality of first groove portions, and an average pitch of the plurality of first groove portions is greater than 0 and equal to or less than 500 μm. Production method. The method of manufacturing an electromagnetic wave shielding filter according to claim 25, wherein an average pitch of the plurality of first groove portions is 200 μm to 400 μm. 25. The method of manufacturing an electromagnetic wave shielding filter according to claim 24, wherein the groove is extended in the oblique line direction. 25. The method for manufacturing an electromagnetic wave shielding filter according to claim 24, wherein an angle formed between the tangent formed by the gravure roll and the blanket roll and the first groove portion is 20 ° to 70 °. One surface includes a tin surface with a relatively large amount of tin distribution, and the other surface has a transparent tempered glass substrate having an air surface with a relatively small amount of tin distribution compared to the tin surface.
An electromagnetic wave shielding member formed in a mesh shape on a tin surface of the transparent tempered glass substrate, and a display device that displays an image and includes a display panel facing the transparent tempered glass substrate,
The electromagnetic wave shielding member is applied to shield electromagnetic waves emitted from the 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. A display device. 30. The display device of claim 29, wherein the transparent tempered glass substrate is manufactured by strengthening a plate glass manufactured by a float method. 30. The display device of claim 29, further comprising: an air surface sequentially formed under the transparent tempered glass substrate so as to be exposed to outside air; a color correction and near-infrared shielding layer; and an antireflection layer. . The display panel is
A first substrate and a second substrate facing each other; and a black layer positioned between the first substrate and the second substrate,
30. The display device according to claim 29, wherein the electromagnetic shielding member intersects the black layer. 30. The display device according to claim 29, wherein the electromagnetic wave shielding member is in contact with the second substrate. 30. The display device according to claim 29, wherein the display panel is a plasma display panel.

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