JP2008083263A - Protective plate for portable display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective plate for a portable display device, having excellent visibility of a transparent window part. <P>SOLUTION: The protective plate for the portable display device is characterized in that a film covering a transparent window part and having a metal thin-film layer formed entirely or partially at a periphery of the transparent window part is stuck to the reverse surface of a tempered glass plate through a glue layer, a transparent coating covering at least the transparent window part is formed on the reverse surface of the film, and the outermost reverse surface of the transparent window part is made of a hard material. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a protective plate used for a portable display device such as a mobile phone or a portable information terminal, and more particularly to a protective plate for a portable display device having excellent visibility of a transparent window portion.

  In an electric apparatus (hereinafter referred to as “portable display device”) having a small display device such as a portable information terminal (PDA) such as a mobile phone and an electronic notebook, a liquid crystal display (LCD), an organic EL device is used as the display device. A flat panel display such as a display, a field emission display (FED), or a plasma display panel (PDP) is used.

  In recent years, in order to display a large amount of information at a time, a display unit in a portable display device is required to be as large as possible within a range that can be used for portable use. Such a tendency is particularly remarkable in the display unit of a mobile phone or a PDA. The increase in the size of the display unit is also demanding an increase in the size of a protective plate used to protect a display element such as a liquid crystal panel. On the other hand, not only an increase in the size of the display unit but also a reduction in size (thinning) and weight reduction of the device are emphasized in the portable display device.

  Therefore, conventionally, a resin plate made of an acrylic resin that is excellent in transparency and lightweight is used as the protective plate. When an acrylic resin plate is used as a protective plate, character information required for the display unit of the portable display device, a decorative pattern, etc. are printed in advance on the surface of the resin plate by silk screen printing or the like. It is also possible. However, since acrylic resin plates generally have low impact resistance, there is a problem that they are easily damaged or damaged by an external impact or load.

  In addition, the acrylic resin plate is processed extremely thin (usually to a thickness of about 0.5 to 1 mm) in order to cope with the reduction in weight and thickness of the portable display device. Insufficient rigidity. Therefore, for example, when the finger is pressed with a finger, the protective plate easily bends, causing contact with a display element such as a liquid crystal panel to disturb the display, and in some cases adversely affecting the function of the element. There is a risk.

  For the purpose of satisfying the contradictory demands of an increase in the size of the image display unit and a reduction in the size of the entire phone, the form of the mobile phone mainly includes a first casing 31 that mainly accommodates the display unit 33 and the receiver unit 34, and A so-called foldable type in which the operation unit 35 and the second transmission unit 36 are accommodated in the operation unit 35 and the transmission unit 36 and these are coupled by a hinge unit 37 is increasing (see FIG. 9). Since such a foldable mobile phone 30 is normally folded with the display unit 33 and the operation unit 35 facing each other, the key 38 of the operation unit 35 or a specific key is used during the opening / closing operation. The protrusion 39 for position confirmation provided on the top surface of the plate 38 and the protective plate 40 of the display unit 33 come into contact with each other, and the protective plate 10 is scratched or broken by repeating this process. Problems are likely to occur.

  A portable display device such as a mobile phone or a PDA has a structure in which the protective plate cannot be easily removed in order to protect the display device and other precision devices from dust and moisture. Moreover, in recent years, portable display devices tend to increase the price and added value of the device itself. Therefore, it is required to reinforce the protective plate itself so that a slight contact or impact does not cause a scratch or breakage that requires replacement of the protective plate.

  In addition, for example, in a mobile phone, the display unit often comes into contact with the cheeks or the like during use, and therefore, there is a problem that dirt due to foundation or sweat easily adheres to the protective plate. In the case of a resin plate, it is difficult to wipe off the dirt due to the characteristics of the resin plate. Furthermore, since the acrylic resin plate is a material that is prone to static electricity, for example, when the surface of the protective plate is printed or mounted on a portable display device, the problem is that dust is likely to adhere, or static electricity. There is also a problem of causing damage to precision instruments such as display devices.

  Therefore, a protective plate having excellent transparency, strength, antifouling properties and handling properties has been devised and disclosed in Patent Document 1. That is, it is a protective plate for a portable display device in which a scattering prevention film is attached to one surface of a tempered glass plate, and a film on which characters or patterns are printed is attached to the same surface. The film 13 is a so-called donut-shaped member in which characters 14 or patterns are printed only on the film base, and the double-sided tape 15 has a shape corresponding to the film portion of the film 13. It is a donut-shaped member (see FIG. 10). This is because when the doughnut-shaped shape, that is, the shape in which the central portion is hollowed out, is formed, it is possible to prevent a decrease in transmittance in a portion where printing is not performed.

JP 2003-140558 A

  However, forming a film on which characters or patterns are printed as in Patent Document 1 with a donut-shaped member is easy to deform because of the donut-shaped member, and the pasting operation is difficult. Therefore, in reality, as shown in FIG. 11, the film covering the entire tempered glass plate 1 is decorated with a frame shape (consent with a donut shape).

  However, in the configuration as shown in FIG. 11, when the entire frame-shaped decoration or a part thereof exhibits a metallic luster by forming a partial metal thin film layer 4, the metal thin film layer 4 is usually used. After forming a solvent-soluble resin layer on the part that does not need to be, a method of removing the unnecessary metal thin film together with the solvent-soluble resin layer by forming a metal thin film on the entire surface and washing the solvent is adopted. If the removal of the solvent-soluble resin layer is insufficient, there is a problem that the skin or the satin pattern appears on the transparent window portion 10a.

  Further, in the configuration as shown in FIG. 11, there is a problem that the exposed surface of the film hitting the transparent window portion 10a is damaged before the protective plate is attached to the portable display device.

  Accordingly, an object of the present invention is to provide a protective plate for a portable display device that solves the above-described problems and is excellent in visibility of a transparent window portion.

  In order to achieve the above object, the protective plate for a portable display device of the present invention covers a transparent window portion on the back surface of a tempered glass plate, and a metal thin film layer is entirely or partially around the transparent window portion. The formed film is affixed with a glue layer, and has a transparent coating film covering at least the transparent window portion on the back surface thereof, and the back surface of the transparent window portion is made of a hard material. I made it.

  The protective plate for a portable display device of the present invention is a film in which a transparent window portion is covered on the back surface of a tempered glass plate, and a metal thin film layer is formed entirely or partially around the transparent window portion, A film having at least a transparent window portion and having a hard coat layer formed on the back surface is sequentially pasted with a glue layer.

  Moreover, in the said structure, the concealing layer was formed in the back surface of the film in which the said hard-coat layer was formed, and the circumference | surroundings of the said transparent window part.

  Moreover, in each said structure, the concealing layer was formed in the back surface of the film in which the said metal thin film layer was formed, and the circumference | surroundings of the said transparent window part.

  The protective plate for a portable display device according to the present invention is a film in which a transparent window portion is covered on the back surface of the tempered glass plate and a metal thin film layer is formed entirely or partially around the transparent window portion. A hard overcoat layer that is affixed with a layer and covers at least the transparent window portion is formed on the back surface thereof.

  In the configuration in which the overcoat layer is formed, a concealing layer is formed on the back surface of the overcoat layer and around the transparent window portion.

  In each configuration in which the overcoat layer is formed, a concealing layer is formed on the back surface of the film on which the metal thin film layer is formed and around the transparent window portion.

  Moreover, in each said structure, the film in which the said metal thin film layer was formed was such that the metal thin film layer was formed in the back surface side of the said film.

  Moreover, in each said structure, the film in which the said metal thin film layer was formed was made to have the said metal thin film layer formed in the surface side of the said film.

  Since this invention consists of an above-described structure, it has the following effects.

  That is, the protective plate for a portable display device of the present invention is a film in which a transparent window portion is covered on the back surface of the tempered glass plate and a metal thin film layer is formed entirely or partially around the transparent window portion. Since the back surface of the film is provided with a transparent coating film that covers at least the transparent window portion, the metal thin film can be formed on any of the front and back surfaces of the film on which the metal thin film layer is formed. Since the patterned surface is covered with the adhesive layer or the coating film, even if the solvent-soluble resin layer is not sufficiently removed by patterning, the fine irregularities formed by the remaining solvent-soluble resin layer are air. Does not interface with the layer. As a result, the protective plate has an effect that the skin or the satin pattern does not appear on the transparent window portion.

  In addition, since the back surface of the transparent window portion is made of a hard material, the back surface of the transparent window portion is not damaged until the protective plate is attached to the portable display device.

  Therefore, a protective plate for a portable display device having excellent visibility of the transparent window portion can be obtained.

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

  The first embodiment of the protective plate 10 for a portable display device shown in FIG. 1 is used with the surface on the tempered glass 1 side arranged on the outside of the display device. On the back surface of the tempered glass plate 1 is a film 3 that covers a transparent window portion 10a and has a metal thin film layer 4 formed around the transparent window portion 10a, and a hard coat layer 7 that covers the transparent window portion 10a and on the back surface. The formed film 6 is stuck on the glue layers 2 and 5 sequentially. In FIG. 1, the film 3 on which the metal thin film layer 4 is formed is such that the partial metal thin film layer 4 is formed on the back side of the film 3, and the hard coat layer 7 is A masking layer 8 is formed on the back surface of the formed film 6 and around the transparent window portion 10a.

  In the protective plate 10 for a portable display device according to the present invention, examples of the portable display device to be protected by the protective plate 10 include a mobile phone, a portable information terminal, a portable game machine terminal, and a portable television receiver. And a device including a small display device that can be used for portable use, such as a digital camera and a video camera. In particular, the protective plate for a portable display device according to the present invention is suitably used in, for example, a display unit 33 in a mobile phone 30 as shown in FIG. 9 or a display unit in a personal digital assistant (PDA) such as an electronic notebook. .

  The material of the tempered glass 1 is not particularly limited, but the use of white soda glass (so-called white glass) rather than general-purpose so-called blue glass further improves mechanical strength and the like. Preferred above. The method for producing tempered glass (the method for tempering) is not particularly limited, but it is preferable to employ a tempering method by ion exchange rather than a tempering method by air cooling. Chemically tempered glass strengthened by ion exchange exhibits a greater compressive stress than air-cooled tempered glass, as described above. Although it does not specifically limit about the thickness of a tempered glass board, From a viewpoint of maintaining sufficient intensity | strength characteristic, aiming at weight reduction, it is preferable to set it as the range of 0.3-1.1 mm, 0 More preferably, it is in the range of 5 to 0.8 mm.

  In the protective plate according to the present invention, a film 3 on which a partial metal thin film layer 4 is formed in advance is attached to the back surface of the tempered glass plate 1 for the purpose of displaying characters and patterns having metallic luster on the protective plate itself. Is done.

  Although the raw material of the said film is not specifically limited, It is preferable that it is a thing excellent in transparency (thing with the high transmittance | permeability), for example, resin films, such as a polyester film, are mentioned. The metal thin film layer 4 is formed by patterning a metal thin film by a vacuum deposition method, a sputtering method, an ion plating method, a plating method or the like. In this case, a metal such as aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead, or zinc, or an alloy or compound thereof is used depending on the metallic luster color to be expressed. As a means for patterning the metal thin film, a solvent-soluble resin layer is formed on a portion where the metal thin film layer 4 is not required, and then a metal thin film is formed on the entire surface, followed by solvent cleaning and a solvent-soluble resin layer. Remove unnecessary metal film. In FIG. 1, the metal thin film layer 4 is formed in the entire periphery of the transparent window portion 10a, that is, in the shape of a frame, but only on a part of the periphery of the transparent window portion 10a. It may be configured to display information such as a company name.

  Moreover, in the protective plate which concerns on this invention, the film 6 by which the hard-coat layer 7 was previously formed in the back surface for the purpose of providing hardness to the outermost back surface of the said transparent window part 10a of a protective plate is the said metal thin film layer 4. Is pasted on the back surface of the film 3 on which is formed.

  Although the raw material of the said film is not specifically limited, It is preferable that it is a thing excellent in transparency (thing with the high transmittance | permeability), for example, resin films, such as a polyester film, are mentioned. The method of forming the hard coat layer 7 on the film and the hard coat ink used are not particularly limited, and various conventionally known hard coat layers used for forming the hard coat layer on the resin film. 7 Forming method, hard coat ink or the like can be employed.

  As the adhesive layers 2 and 5 used for pasting each film, various conventionally known materials used for pasting on a resin film, such as pressure-sensitive adhesive (Pressure-Sensitive-Adhesive: abbreviation PSA), A UV adhesive or the like can be employed. When a UV adhesive is used, a smooth surface can be maintained by curing the coating film surface in a smooth and even state.

  In the embodiment of FIG. 1, since the back surface of the film 3 on which the metal thin film layer 4 is formed, that is, the surface on which the metal thin film is patterned is covered with the glue layer 5, it is not possible to remove the solvent-soluble resin layer by patterning. Even if it is sufficient, fine unevenness formed by the remaining solvent-soluble resin layer does not become an interface with the air layer. Therefore, in this structure, the effect that a hull or a satin pattern does not appear in the transparent window part 10a is acquired.

  Moreover, in the protective plate which concerns on this invention, the concealing layer 8 is formed in the back surface of the film 6 in which the said hard-coat layer 7 was formed in order to conceal the circumference | surroundings of the said transparent window part 10a of a protective plate. The concealment layer 8 is for concealing the circuit and the like by covering the periphery of the transparent window portion 10a with a frame portion and improving the design. For example, in the case of a protective plate used in a display unit of a mobile phone, solid printing (usually coloring or pattern printing in consideration of design) is performed on the peripheral portion so as to prevent the internal structure of the device from being seen. Applied. When the metal thin film layer 4 covers the entire periphery of the transparent window portion 10, the concealing layer 8 can be omitted, but the concealing layer 8 is present on the back side of the metal thin film layer 4. This is preferable because the concealability is further improved. The method for forming the masking layer 8 and the masking coloring ink used are not particularly limited, and various conventionally known printing methods and masking used for forming the masking printing layer on the resin film. Can be used.

  Further, the masking layer 8 may be formed on the back surface of the film 6 on which the hard coat layer 7 is formed and around the transparent window portion 10a (see FIGS. 1 and 2), or the metal thin film layer. 4 may be formed on the back surface of the film 3 on which the film 4 is formed and around the transparent window portion 10a (see FIGS. 3 and 4).

  The portable display device protective plate 10 according to the present invention has a configuration in which the transparent thin film portion 10a is covered on the back surface of the tempered glass 1 and the metal thin film layer 4 is entirely or partially around the transparent window portion 10a. The film 3 formed on is attached with a glue layer, and has a transparent coating film covering at least the transparent window portion 10a on the back surface thereof, and the back surface of the transparent window portion 10a is made of a hard material. What is necessary is just and it is not limited to said 1st embodiment. For example, a film in which the transparent window portion 10a is covered and the metal thin film layer 4 is formed around the transparent window portion 10a is attached to the back surface of the tempered glass plate 1 with the adhesive layer 2, and the above-mentioned hard Instead of sticking the film 6 on which the coat layer 7 is formed (see FIG. 1), a hard overcoat layer 9 that covers at least the transparent window portion 10a may be formed (second embodiment). Form: see FIG. In addition, about the structure which is common in 1st embodiment, since it is the same, description is abbreviate | omitted.

  The hard overcoat layer 9 is formed for the purpose of imparting hardness to the outermost surface of the transparent window portion 10a of the protective plate, similar to the film 6 on which the hard coat layer 7 is formed. The same effect as the glue layer 5 which is a transparent coating film covering the surface of the film 3 on which the metal thin film is patterned is obtained. That is, in the second embodiment, the back surface of the film 3 on which the metal thin film layer 4 is formed, that is, the surface on which the metal thin film is patterned is covered with the overcoat layer 9, so that the solvent-soluble resin layer is removed by patterning. Even if this is insufficient, the fine irregularities formed by the remaining solvent-soluble resin layer do not form an interface with the air layer. Therefore, in this structure, the effect that a hull or a satin pattern does not appear in the transparent window part 10a is acquired. As a method for forming the overcoat layer 9, a potting method, a coating method, a screen printing method, or the like is used. Further, as the overcoat ink to be used, an acrylic resin which is a highly transparent type of thermoplastic resin can be employed in addition to the same as the hard coat layer described above.

  Also in the second embodiment, as in the first embodiment, a concealing layer 8 is formed on the back surface of the overcoat layer 9 for the purpose of concealing the periphery of the transparent window portion 10a of the protective plate. Since the description of the hiding layer 8 is the same as in the first embodiment, a description thereof will be omitted.

  Further, the masking layer 8 may be formed on the back surface of the film 6 on which the hard coat layer 7 is formed and around the transparent window portion 10a (see FIGS. 5 and 6), or the metal thin film layer. 4 may be formed on the back surface of the film 6 on which the film 4 is formed and around the transparent window portion 10a (see FIGS. 7 and 8).

  In the protective plate according to the present invention, the film 3 on which the metal thin film layer 4 is formed may have the metal thin film layer 3 formed on the back side of the film 3 (FIG. 1). , FIG. 3, FIG. 5 and FIG. 7), the film 3 on which the metal thin film layer 4 is formed may have the metal thin film layer 4 formed on the surface side of the film 3 (FIG. 2). FIG. 4, FIG. 6 and FIG. 8). In the latter case, the surface of the film 3 on which the metal thin film layer 4 is formed, that is, the surface on which the metal thin film is patterned is covered with the glue layer 2 and the tempered glass plate 1. Even if the removal of the layer is insufficient, the fine unevenness formed by the remaining solvent-soluble resin layer does not become an interface with the air layer. Therefore, in this structure, the effect that a hull or a satin pattern does not appear in the transparent window part 10a is acquired.

  In addition, since the film on which the metal thin film layer 4 or the masking layer 8 is formed has a step between the metal thin film layer 4 or the portion where the masking layer 8 is formed and the non-formed portion, the surface having the step is formed. When the glue layers 2 and 5 are formed, the glue layers 2 and 5 are formed with a thickness that can sufficiently fill the steps. In this invention, it is 20 micrometers or more, for example. This is because if the step cannot be sufficiently filled, the air may be bitten.

  It is to be noted that, by appropriately combining any of the various embodiments, the effects possessed by them can be produced. Although the present invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various variations and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as long as they do not depart from the scope of the present invention.

(Example 1)
First, a metal thin film layer made of aluminum was formed in a frame shape on one surface of a PET film having a thickness of 38 μm so as to constitute a transparent window portion at the center. The metal thin film layer is patterned by forming a solvent-soluble resin layer made of a precipitated barium sulfate resin on a portion where the metal thin film layer is not required, and then vacuum-depositing the metal thin film made of the metal on the entire surface. And was washed with water to remove the unnecessary metal thin film together with the solvent-soluble resin layer.

  Further, a hard coat layer made of an acrylic resin is entirely formed on one surface of another 38 μm-thick PET film by a roll coating method, and a transparent window portion is formed on the central portion thereof. A concealing layer was formed in a frame shape by screen printing using an ink containing a black pigment in a resin binder made of two-component curable urethane.

  Next, high strength glass “Cristana” manufactured by Ishizuka Glass Co., Ltd. was prepared as a tempered glass plate having a thickness of 0.5 mm, and the metal thin film layer was formed on the back surface of the film on which the metal thin film layer was formed. The adhesive layer was affixed with PSA so that the surface would be the back surface. Next, the film on which the hard coat layer and the concealing layer are formed is pasted on the back surface of the pasted product with the adhesive layer made of PSA so that the surface on which the hard coat layer and the concealing layer are formed is the back surface. Thus, the protective plate for display device shown in FIG. 1 was obtained.

(Example 2)
After obtaining a film in which a metal thin film layer was formed in the same manner as in Example 1, a hard overcoat layer made of an acrylic resin covering the entire surface on which the metal thin film layer was formed was formed by a roll coating method. did. Next, a concealing layer was formed in a frame shape in the same manner as in Example 1 so that a transparent window portion was formed in the center portion.

  Next, Ishizuka Glass Co., Ltd. high-strength glass `` Cristana '' is prepared as a tempered glass plate with a thickness of 0.5 mm, and a film on which the metal thin film layer, overcoat layer and concealing layer are formed on the back surface, A protective plate for a display device shown in FIG. 5 was obtained by pasting with a paste layer made of PSA so that the surface on which each layer was formed was the back surface.

  The protective plates for portable display devices obtained in Example 1 and Example 2 were all excellent in the visibility of the transparent window portion.

It is sectional drawing which shows one Embodiment of the protection plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is sectional drawing which shows other embodiment of the protective plate for portable display apparatuses which concerns on this invention. It is a perspective view which shows an example of a folding-type mobile phone. It is a disassembled perspective view which shows the protective plate for portable display apparatuses described in patent documents. It is sectional drawing which shows an example of the protective plate for portable display apparatuses which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tempered glass board 2 Adhesive layer 3 Film 4 Metal vapor deposition layer 5 Adhesive layer 6 Film 7 Hard coat layer 8 Concealment layer 9 Overcoat layer 10 Protection board for portable image display devices 10a Transparent window part 11 Tempered glass board 12 Scatter prevention film 13 Film 30 Mobile phone 33 Display unit

Claims (9)

1. On the back surface of the tempered glass plate, a film that covers the transparent window portion and has a metal thin film layer formed entirely or partially around the transparent window portion is pasted with a glue layer, and the transparent window portion is attached to the back surface of the tempered glass plate. A protective plate for a portable display device, comprising a transparent coating film covering at least, and the rearmost surface of the transparent window portion being made of a hard material.
2. A film in which a transparent window portion is covered and a metal thin film layer is formed entirely or partially around the transparent window portion on the back surface of the tempered glass plate, and at least the transparent window portion is covered and a hard coat layer is formed on the back surface. The protective plate for a portable display device according to claim 1, wherein the applied films are sequentially attached with a glue layer.
3. The protective plate for a portable display device according to claim 2, wherein a concealing layer is formed on the back surface of the film on which the hard coat layer is formed and around the transparent window portion.
4. The protection board for portable display apparatuses in any one of Claim 2 or 3 with which the concealing layer was formed in the back surface of the film in which the said metal thin film layer was formed, and the circumference | surroundings of the said transparent window part.
5. On the back surface of the tempered glass plate, a film that covers the transparent window portion and has a metal thin film layer formed entirely or partially around the transparent window portion is pasted with a glue layer, and the transparent window portion is attached to the back surface of the tempered glass plate. The protective plate for a portable display device according to claim 1, wherein at least a hard overcoat layer is formed.
6. The protective plate for a portable display device according to claim 4, wherein a concealing layer is formed on the back surface of the overcoat layer and around the transparent window portion.
7. The protective plate for a portable display device according to claim 5, wherein a concealing layer is formed on the back surface of the film on which the metal thin film layer is formed and around the transparent window portion.
8. The protective plate for a portable display device according to claim 2, wherein the film in which the metal thin film layer is formed is a film in which the metal thin film layer is formed on the back side of the film.
9. The protective plate for a portable display device according to claim 2, wherein the film in which the metal thin film layer is formed is one in which the metal thin film layer is formed on a surface side of the film.

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