KR20050033971A - Emi shielding film for improving color gamut and plasma display device employing the same - Google Patents

Abstract

Provided is an EMI shielding film for improving color gamut which shows EMI shielding effect and color gamut advancing effect by a piece of paper to reduce the number of joining and additional processes in producing a filter, thereby it makes ease of attaching the filter to a PDP panel directly. The EMI shielding film for improving color gamut comprises the parts of: a transparent substrate(21); an adhesive layer(22) which is formed in the upper side of the transparent substrate; messy metallic patterns(23) which are formed in the upper side of the adhesive layer; and a transparent selective absorbing layer which is placed between the messy metal patterns having a transparent material and a selective absorbing material.

Description

Electromagnetic shielding film for improving color and plasma display device employing the same {EMI shielding film for improving Color Gamut and plasma display device employing the same}

The present invention relates to an electromagnetic wave shielding film for color enhancement and a plasma display device employing the same, and more particularly, to an electromagnetic wave shielding film and a plasma display device employing the same, as well as electromagnetic shielding. will be.

The plasma display device is a thin, light-emitting display device that is easy to be enlarged as compared with other image display devices, and is considered to have the most suitable characteristics for high-quality digital television. However, the plasma display device has a problem in that color purity characteristics are deteriorated due to unnecessary light emission of near infrared rays caused by plasma generated by plasma light emission and circuits and plasma of an inert gas used for screen emission. Therefore, a filter is installed on the front surface of the plasma display device in order to not only prevent harmful effects of the human body due to electromagnetic waves and near infrared rays generated in the plasma display device and malfunction of precision instruments, but also to reduce surface reflection and improve color purity.

The filter used in the plasma display device generally uses a method of treating a conductive film or a metal mesh on a transparent glass or plastic substrate, and laminating a near infrared ray blocking and antireflective film. Ground through the chassis.

1 is a diagram schematically illustrating a structure of a plasma display device employing a general filter. Referring to this, the front filter 11 is installed on the front surface of the PDP panel and the driving circuit 10. At this time, the front filter 11 has an anti-reflection layer 13 formed on the glass or plastic substrate 12, and an electromagnetic wave shielding layer 14 and near-infrared rupture and selective wavelength on the glass or plastic substrate 12. The absorbent film 15 has a structure in which the absorber films 15 are sequentially stacked. The PDP panel and drive circuit 10 and the front filter 11 are housed in a case 16.

As another filter employable on the front surface of the plasma display device, a mesh film 20 as shown in FIG. 2 is known.

2, the adhesive layer 22 is formed on the transparent base material 21, and the mesh-like metal pattern 23 is formed in the upper part. By the way, in such a mesh film, there exists a possibility that the metal pattern of a base material and a mesh shape may separate or damage. In addition, when bonding to another film or glass without filling the empty space between the metal patterns, diffuse reflection occurs due to the formation of an air layer between the film and the bonded substrate, causing the image to appear blurred. Therefore, it is necessary to fill the mesh film with a transparent material in the empty space before attaching it to another substrate. In addition, in order to apply such a mesh film to a plasma display device, a dye-containing film capable of blocking near-infrared rays was separately prepared, and a method of bonding the mesh film to the upper portion of the mesh film of FIG. 2 was used.

However, according to this method, there is a disadvantage in that the manufacturing process of the filter is long and cumbersome, and in addition, there is much room for improvement such as reduction of haze, transmittance and contrast.

The technical problem to be achieved by the present invention is to provide an electromagnetic shielding film and a plasma display device employing the electromagnetic shielding film that can improve the color sense function and contrast, as well as electromagnetic shielding.

In the present invention to achieve the first technical problem,

Transparent substrates;

An adhesive layer formed on the transparent substrate;

A mesh-shaped metal pattern formed on the adhesive layer; And

It is formed between the metal pattern of the mesh on the adhesive layer, and provides an electromagnetic shielding film for improving the color comprising a transparent selective light absorbing layer comprising a transparent material and a selective light absorbing material.

Another technical problem of the present invention is achieved by a plasma display device employing the above-described electromagnetic wave shielding film for improving color.

Hereinafter, the manufacturing process of the electromagnetic wave shielding film for improving the color of the present invention will be described.

First, an adhesive layer is formed on the transparent substrate, and then a patterned mesh metal pattern is laminated on the adhesive layer. Here, the transparent substrate is a polyethylene terephthalate film (PET), TAC (Tri-acetyl-cellulose), Polyvinyl alcohol (PVA), polyethylene (PE) and the like are used, and the thickness thereof is preferably 10 to 1000 µm, and 50 to 500 µm. The mesh metal pattern is formed using a material selected from the group consisting of Ag, Cu, Ni, Al, Au, Fe, Pt, Cr. The adhesive layer is formed using an adhesive, and specific materials thereof include UV adhesives such as thermosetting agents, acrylic resins, polyester resins, and epoxy resins, and acrylic, urethane, and epoxy-based transparent adhesives. And the thickness of an adhesive layer is 1-1000 micrometers, and it is preferable that it is about 10-500 micrometers.

As a method of forming the filter having the mesh-like metal pattern described above, a method of forming a lattice mesh pattern by attaching a thin copper metal sheet to an upper portion of a polyethylene terephthalate substrate using an adhesive, followed by etching, glass, After forming a pattern on a film and a metal substrate, the method of using a plating method, the method of using a metallic fiber mesh, the printing method, etc. can be used.

The transparent material and the selective light absorbing material are mixed between the metal patterns on the mesh and are screen-printed, using a table coater, a cap coater, a bar coater, a blade, and the like. After application, it is heat treated for drying and curing to form a transparent selective light absorbing layer. As said transparent substance, the thing of 90% or more of transmittance | permeability is used as a colorless transparent substance. These include UV curing agents, UV adhesives, thermal curing agents, binders, adhesives, and the like, and specific examples thereof include polyester resins, thiol-olefin resins, acrylic resins, epoxy resins, urethane resins, and other binders. Can be mentioned. As the selective light absorbing material, a material capable of selectively absorbing light having a wavelength of 300 to 1200 nm, in particular, a Ne absorbing material or a near-infrared light absorbing material is used. As a specific compound thereof, as a Ne absorbing material, porphyrin-based and squaaryl And a cyanine-based substance. Examples of the near-infrared absorbing substance include metal complexes, immonium-based, phthalocyanine-based, cyanine-based, anthraquinone-based and dithiol-based.

The content of the selective light absorbing material is based on 100 parts by weight of the transparent material. It is preferable that it is 0.05-20 weight part. If the content of the selective light-absorbing material is less than 0.05 parts by weight, the absorbance is low, the color reproduction range of the appropriate level and the near infrared transmittance is high, the malfunction occurrence rate of the electronic product is increased, and if it exceeds 20 parts by weight, it is not preferable because the overall transmittance is lowered.

The drying and heat treatment process may be UV curing, IR curing, thermosetting or drying using heat and wind. If the coating state of the film after coating is not good, it is preferable to uniformly coat the coating film using a substrate having a uniform surface (eg, film, glass), and then go through a drying and post-treatment process.

It is preferable that the film thickness of the transparent selective light absorbing layer 34 is 1 μm to 1000 μm. If the film thickness is less than 1 μm, it is difficult to coat with a uniform thickness, the absorption rate is low, it is difficult to implement a suitable level of color reproduction range, it is difficult to show a sufficient effect in terms of near infrared absorption. If the thickness exceeds 1000 μm, bubble problems may occur in the post-treatment process, and the coating layer may be cracked, which is not preferable.

The electromagnetic wave shielding film for improving color of the present invention has a transmittance of 40 to 80%, particularly 45 to 70%, and a color temperature of 6000 to 20000K, in particular, 9000 to 15000K, conductivity of 0.5 ohm / square or less, and a red color coordinate range x of 0.58 to 0.72. And y is within 0.2 to 0.4, and particularly preferably x 0.64 to 0.70, and y is within 0.24 to 0.32.

3 shows the structure of the electromagnetic wave shielding film 30 of the present invention formed in the above-described process.

Referring to FIG. 3, an adhesive layer 32 is formed on the transparent substrate 31, and a patterned mesh metal pattern 32 is stacked thereon. A transparent selective light absorbing layer 34 including a transparent material and a selective light absorbing material is formed between the metal conductive layers 32.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

Example 1

A thin Cu metal plate was attached to the polyethylene terephthalate by using a thermosetting agent, which is a metal adhesive, and then etched according to a predetermined pattern to form a mesh metal pattern.

100 g of a UV curing agent added with a photoinitiator to a monomer as a transparent substance and 3 g of an imonium-based (Japanese powder PDC-220), a Ne absorbing dye, are mixed and screen-printed using this mixture to transparently absorb light between the metal patterns of the mesh. The electromagnetic wave shielding film was manufactured by applying the layer forming composition and forming a transparent selective light absorbing layer using light having a wavelength of 240 to 450 nm.

 Example 2

When forming the transparent selective light-absorbing layer, it was carried out in the same manner as in Example 1, except that 100 g of UV curing agent, which is a transparent substance, and 1 g of a metal complex system (Mitsui SIR-128) were added to the immonium, which is a Ne absorbing dye. An electromagnetic wave shielding film was prepared.

Comparative Example 1

After attaching a thin Cu metal plate on the polyethylene terephthalate by using a thermosetting agent as an adhesive, it was etched according to a predetermined pattern to form a mesh metal pattern.

100 g of a UV curing agent, which is a transparent material, was screen-printed to apply a transparent coating film between the metal patterns on the mesh, and to form a transparent coating film using light having a wavelength of 240 to 450 nm to prepare an electromagnetic wave shielding film.

In the electromagnetic shielding film prepared according to Example 1-2 and Comparative Example 1, the light spectrum was examined, the results are shown in FIG.

Referring to FIG. 4, the relative intensity of the PDP light source can be seen, and since the reduction ratio of the unnecessary wavelength band (590 nm) outside the RGB center wavelength is large, color purity can be improved, and the display can reproduce a range of reproducible color reproduction. By increasing the absorption rate of ~ 1100nm, it can be seen that malfunctions can be prevented when using electronic products and remote controls.

In the electromagnetic shielding film prepared according to Example 1-2 and Comparative Example 1, color temperature, color reproduction range and color coordinate characteristics were examined, and the results are shown in Table 1 below.

division Transmittance (%) Conductivity (Ω / sq) Color temperature (K) Color reproduction range R G B x y x y x y Comparative Example 1 83% 0.2 6980 0 0.631 0.358 0.264 0.658 0.264 0.658 Example 1 53% 0.2 12610 12.27 0.647 0.337 0.237 0.666 0.157 0.088 Example 2 51% 0.2 12820 12.64 0.645 0.338 0.236 0.667 0.156 0.090

As can be seen from Table 1, the electromagnetic shielding film of Example 1-2 was found to improve the color temperature, color gamut and color coordinate characteristics compared to the case of Comparative Example 1.

The electromagnetic wave shielding film of the present invention not only improves color compared with the conventional mesh film, but also improves contrast characteristics. In addition, one film is equipped with electromagnetic shielding function and color enhancement function, which can reduce the number of times of joining and additional work process compared to the existing method when manufacturing a filter. It has the advantage of being easy.

1 is a view schematically showing a structure of a plasma display device employing a general filter,

2 is a view schematically showing the structure of a filter for a plasma display device according to the prior art,

3 is a view schematically showing the structure of the electromagnetic shielding film for improving the color of the present invention,

4 is a view showing the light spectrum of the electromagnetic shielding film prepared according to Example 1-2 and Comparative Example 1 of the present invention.

<Brief description of the major symbols in the drawings>

11 ... front filter 12 ... glass or plastic substrate

13 ... Antireflection layer 14 ... Electromagnetic shielding layer

15. NIR and selective wavelength absorption film

16 ... case 20, 30 ... film

21, 31 ... transparent substrate 22, 32 ... adhesive layer

23, 33 ... metal pattern on mesh 34 ... transparent selective light absorbing layer

Claims (8)

Transparent substrates; An adhesive layer formed on the transparent substrate; A mesh-shaped metal pattern formed on the adhesive layer; And The electromagnetic wave shielding film for color improvement, which is formed between the metal pattern on the upper surface of the adhesive layer and comprises a transparent selective light absorbing layer containing a transparent material and a selective light absorbing material. The electromagnetic wave shielding film according to claim 1, wherein the transmittance is 45 to 70%, the color temperature is 9000 to 15000K, the conductivity is 0.5 ohm / square or less, the red color coordinate range x is 0.64 to 0.70, and y is 0.24 to 0.32. The method of claim 1, wherein the selective light-absorbing material is a material capable of selectively absorbing light having a wavelength of 300 to 1200nm wavelength color enhancement electromagnetic shielding film, characterized in that. The group of claim 3, wherein the material capable of selectively absorbing light having a wavelength of 300 to 1200 nm is selected from the group consisting of porphyrin-based, squarylium-based, rhodamine-based, cyanine-based, phthalocyanine-based, immonium-based, anthraquinone-based and dithiol-based. Color-improving electromagnetic wave shielding film, characterized in that at least one selected from. The electromagnetic wave shielding film of claim 1, wherein the transparent material is one selected from a polyester resin, a thiol-olefin resin, an acrylic resin, an epoxy resin, and a urethane resin. The method of claim 1, wherein in the transparent selective light-absorbing layer, the content of the selective light-absorbing material is 0.05 to 20 parts by weight based on 100 parts by weight of the transparent material, characterized in that the color shielding electromagnetic wave shielding film. The electromagnetic wave shielding film for color improvement according to claim 1, wherein the transparent selective light absorbing layer has a thickness of 1 µm to 50 mm. The plasma display apparatus which employ | adopted the electromagnetic shielding film for color improvement of any one of Claims 1-7.