JP4154717B2 - Electromagnetic wave cut filter - Google Patents

Description

  The present invention relates to an electromagnetic wave cut filter that shields electromagnetic waves generated from the front surface of a screen while ensuring the visibility of a liquid crystal screen or a CRT.

  In recent years, the influence on the human body due to electromagnetic waves leaking from the front surface of a screen such as a mobile phone screen or a CRT display has been regarded as a problem. The following Patent Documents 1 and 2 will be described as conventional examples of the electromagnetic wave cut filter provided on the front surface of the screen for shielding such electromagnetic waves.

  Patent Document 1 uses a conductive substance to improve visibility by preventing reflection of a CRT screen or the like and to shield electromagnetic waves. The structure is a conductive reflective film in which three or more antireflective films including at least one conductive layer are formed on a transparent substrate made of a plastic film, wherein the antireflective film is the conductive layer. It consists of a refractive index layer and a low refractive index layer other than the conductive layer.

  In such a structure, the low refractive index layer is made of silicon oxide, and the low refractive index layer is formed by a vacuum deposition method. The high refractive index layer is made of ITO, and the high refractive index layer is formed by a sputtering method. With such a configuration, it is said that a shield material having excellent adhesion and scratching properties of the film and having a hardness that does not cause cracks can be manufactured relatively easily.

  Patent Document 2 was made to obtain a shielding material having good visibility and sufficient electromagnetic wave shielding function in order to prevent electromagnetic waves generated from a large screen of a recent PDP (plasma display panel). Is.

The structure is characterized in that, in a shield material having a metal foil pattern on one surface of a transparent substrate, both surfaces and side surfaces of the metal foil pattern are blackened. Since the pattern screen and the side surface are blackened, it is possible to suppress light emitted from the surface screen of the PDP and incidence from the outside. Moreover, said metal foil is patterned by an etching through an adhesive bond layer.
JP-A-10-161553 (first and second pages) JP 2002-9484 A (pages 1 and 2)

  In Patent Document 1 or Patent Document 2 described above, a conductive layer for preventing electromagnetic waves is formed by vacuum deposition or sputtering, and a metal foil is formed by etching.

  In contrast, the present invention employs a method for forming a conductive layer by simpler printing, thereby ensuring the visibility of liquid crystal screens, CRTs, etc., and improving the electromagnetic waves generated from the front of those screens. An object of the present invention is to provide an electromagnetic wave cut filter which is shielded.

In order to achieve the above object, the electromagnetic wave cut filter according to the present invention has a line width of a mesh pattern in which a mesh made of silver paste is arranged in an inclined manner on one surface of an upper surface or a lower surface of a transparent synthetic resin substrate. A synthetic resin film is formed through a transparent adhesive layer that is formed by screen printing in a range of 30 μ to 50 μ and an aperture ratio of 80% to 90%, and covers a mesh pattern of silver paste formed on one surface of the synthetic resin substrate. In the electromagnetic wave cut filter in which the release paper is bonded to the lower surface of the synthetic resin substrate via a releasable adhesive layer, the mesh pattern is formed by screen printing with a silver paste thickness of 4 to 7 μm. In addition, the rectangular cut line provided inside the outer periphery of the electromagnetic wave cut filter is designed to be a predetermined pasting part. The features.

  According to the electromagnetic wave cut filter of the present invention, a mesh pattern with a line width of 30 μ to 50 μ is formed by screen printing on the upper surface of a transparent synthetic resin substrate, and the mesh pattern with a line width of 30 μ to 50 μ is formed. By forming the aperture ratio in the range of 80% to 90%, it is possible to ensure good visibility with respect to the screen and to obtain high electromagnetic shielding performance.

  In addition, by attaching the release paper to the lower surface of the synthetic resin substrate via the removable adhesive layer, the adhesive layer can be protected and the initial adhesive force can be secured.

  Furthermore, since the mesh-shaped pattern openings made of silver paste are arranged in a slanted manner, the mesh-shaped pattern can obtain good visibility that is unlikely to hinder vision.

  Embodiments of the present invention will be described below with reference to the drawings.

  As shown in FIG. 2, the electromagnetic wave cut filter of the present invention is obtained by forming a mesh pattern 3 having a line width of 30 μ to 50 μ with a silver paste on the upper surface of a transparent synthetic resin substrate 2 by screen printing.

  FIG. 1 is a top view of an electromagnetic wave cut filter 1 formed according to the present invention, and a rectangular cut line 4 provided inside along the outer periphery of one electromagnetic wave cut filter 1 is a screen of a mobile phone or the like. A portion (referred to as “sticking portion 5”) that is pasted on the surface is defined in terms of shape, and the portion around it is picked and held by the fingertip when the inner sticking portion 5 is peeled off (“pressing portion”) 6 ”).

  The electromagnetic wave cut filter 1 of the present invention will be described in detail. As shown in FIG. 2, the cross-sectional structure is such that a mesh pattern 3 made of silver paste is formed on the upper surface of a transparent synthetic resin substrate 2, and this mesh A synthetic resin film 8 is bonded to the uppermost surface via a transparent adhesive layer 7 that covers the pattern 3. Further, a release paper 10 is bonded to the lower surface of the synthetic resin substrate 2 via a releasable adhesive layer 9.

  In the cross-sectional configuration described above, it is desirable to use a transparent PET (polyethylene terephthalate) having a thickness of about 100 μm as the synthetic resin substrate 2.

  Further, the mesh pattern 3 made of silver paste formed on the upper surface of the synthetic resin substrate 2 is obtained by forming a linear shape with a silver paste having a line width of 30 μm to 50 μm into a mesh shape by screen printing. The reason why the line width is set to 30 μm to 50 μm is that the thinner the line width is, the better the transmittance is. However, when the silver paste is formed into a linear shape by screen printing, the width of about 30 μm is required due to screen printing performance. If the line width exceeds 50 μm, the visibility of the screen tends to hinder the field of view. Further, the thickness of the silver paste obtained by screen printing is stable when it is about 4 to 7 μm.

  Further, the upper surface of the synthetic resin substrate 2 is coated with a mesh-like pattern 3 made of silver paste by forming an adhesive layer 7 made of highly transparent acrylic glue having a thickness of about 20 μm. In addition to preventing oxidation, it protects against external scratches and damage. Furthermore, a synthetic resin film 8 of about 16 μm made of PET (polyethylene terephthalate) having good transparency is adhered to the upper surface of the adhesive layer 7 to obtain a finished surface.

  On the other hand, an adhesive material layer 9 made of a releasable silicon glue is formed on the lower surface of the synthetic resin substrate 2 with a thickness of about 60 μm. During storage, the adhesive material layer 9 has a thickness of about 75 μm through the adhesive material layer 9. The release paper 10 is adhered so that the pressure-sensitive adhesive layer 9 is protected from the outside air and other articles so as to protect the pressure-sensitive adhesive layer 9.

  In the above configuration, it is preferable to form the mesh pattern 3 having a line width of 30 μm to 50 μm in an aperture ratio range of 80% to 90%. Therefore, in order to set the pitch P of the openings 11, as shown in FIG. 3, the mesh-shaped one section 13 may be taken out and considered. In this one section 13, when a line 12 made of silver paste is formed vertically and horizontally with a line width t, in order to obtain an aperture ratio of 85%, the area occupied by the line 12 made of silver paste shown in black and the other white are used. The line width t in one section may be set so that the ratio of the area occupied by the opening 11 shown is 15:85.

  The square aperture ratio of the mesh pattern 3 having a line width of 30 μ to 50 μ is set to 80% to 90%. When the desirable aperture ratio is 85%, the range of the aperture ratio in consideration of errors due to screen printing. Is set. Therefore, it has been confirmed by experiments that the electromagnetic wave shielding performance when the aperture ratio is 85% is 90% for 20 dB, 99% for 40 dB, and 99 and 6% for 60 dB. It can be understood that high electromagnetic wave shielding performance can be exhibited.

  Moreover, as shown in FIG. 4, it is preferable that the mesh pattern 3 has a mesh in which each opening portion 11 forms a square and is arranged in an inclined manner by 45 °, for example. The reason why the mesh pattern 3 is arranged in an inclined manner as described above is that the mesh shape is not inclined and the horizontal lines are horizontal to each other and the vertical lines are squared by squares perpendicular to the horizontal lines. This is because the alignment of each line is easy to perceive and is not easy to see, which is disadvantageous in terms of visibility. On the other hand, if the mesh pattern 3 is arranged in an inclined manner of 45 °, for example, as described above, it is difficult to enter the vision and it is advantageous in terms of visibility.

  The mesh pattern 3 made of the silver paste of the present invention has a mesh shape with square eyes, but may have a regular hexagonal honeycomb shape or other geometric pattern.

  As shown in FIG. 5, the electromagnetic wave cut filter 1 ′ of this example is formed by screen-printing a mesh pattern 3 having a line width of 30 μ to 50 μ using a silver paste on the lower surface of a transparent synthetic resin substrate 2. In the first embodiment, the mesh pattern 3 is formed on the upper surface of the synthetic resin substrate 2. However, in this embodiment, the mesh pattern 3 is provided on the lower surface of the synthetic resin substrate 2, and thus the same as the above embodiment. In addition, the electromagnetic wave shielding performance can be satisfactorily exhibited.

  Also in the electromagnetic wave cut filter 1 ′ of this embodiment, the synthetic resin film 8 is adhered to the uppermost surface via the transparent adhesive layer 7 covering the mesh pattern 3 as in the first embodiment, while the synthetic resin substrate 2 The release paper 10 is bonded to the lower surface of the adhesive layer 9 via a releasable adhesive layer 9 so as to cover the mesh pattern 3. In use, the pressure-sensitive adhesive layer 9 can be attached to the screen of a mobile phone by peeling off the release paper 1.

  As described above, the present invention can be used as an electromagnetic wave cut filter that shields electromagnetic waves generated from the front surface thereof while ensuring the visibility of a liquid crystal screen, a CRT, etc. It can be used by attaching it to a location where electromagnetic waves should be shielded, such as a screen of a CRT display.

It is a top view of the electromagnetic wave cut filter of Example 1 by this invention. It is a fragmentary sectional view of the electromagnetic wave cut filter of Example 1 by the present invention. It is an enlarged view which shows 1 division of the electromagnetic wave cut filter of Example 1 by this invention. It is the elements on larger scale which show the plane of the electromagnetic wave cut filter of Example 1 by this invention. It is a fragmentary sectional view of the electromagnetic wave cut filter of Example 2 by the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1 '... Electromagnetic wave cut filter 2 ... Synthetic resin substrate 3 ... Mesh pattern 4 ... Cut line 5 ... Pasting part 6 ... Pressing part 7 ... Transparent adhesive material layer 8 ... Synthetic resin film 9 ... Adhesive material layer 10 ... Release paper DESCRIPTION OF SYMBOLS 11 ... Opening part 12 ... Linear 13 ... 1 division P ... Pitch t ... Line width

Claims (1)

A mesh pattern in which a square mesh made of silver paste is arranged on an upper surface or a lower surface of a transparent synthetic resin substrate in an inclined manner by screen printing in a range of a line width of 30 μ to 50 μ and an aperture ratio of 80% to 90%. A synthetic resin film is bonded via a transparent adhesive material layer that covers and forms a mesh pattern of a silver paste formed on one surface of the synthetic resin substrate, and a releasable adhesive material on the lower surface of the synthetic resin substrate In an electromagnetic wave cut filter with release paper adhered through a layer,
The mesh pattern is formed by screen printing with a silver paste thickness of 4-7 μm,
An electromagnetic wave cut filter characterized in that a rectangular cut line provided inside the outer periphery of the electromagnetic wave cut filter is a predetermined pasting portion.

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