Patent Grant
8246412
1. Field of the Invention
The present invention relates to a manufacturing method for a display in which a transparent plate for improving shock resistance, display performance, and so on, for example, is adhered to an outer surface of a screen provided on a display main body.
2. Description of the Related Art
A method disclosed in Japanese Patent Application Publication No. 2000-053453 is known as a method of adhering a transparent plate (sheet glass) for improving shock resistance, display performance, and so on to an outer surface of a screen provided on a display main body. In this method, an adhesive is applied to either one of the screen of the display main body or the transparent plate, whereupon the transparent plate, which is bent so as to project toward the screen of the display main body, is gradually adhered from one side thereof toward an opposite side while applying pressure with a roller.
However, in the method described in Japanese Patent Application Publication No. 2000-053453, a surface of the transparent plate is pressed against the screen of the display main body by the roller, and therefore a load is likely to act on the screen. The load applied to the screen of the display main body may cause a plate material constituting the screen to distort, thereby damaging the plate material itself and members on the inside thereof. Moreover, the transparent plate is easily damaged during the bending process and by the pressing load applied by the roller.
The present invention provides a manufacturing method for a display in which a transparent plate can be adhered to a screen of a display main body substantially without applying a load to the screen and the transparent plate.
The present invention provides a manufacturing method for a display in which a transparent plate is adhered to an outer surface of a screen provided on a display main body, comprising the steps of: setting the outer surface of the screen of the display main body and one surface of the transparent plate as respective adhesion surfaces, and performing a surface treatment in a peripheral edge region of one or both of the adhesion surfaces such that a surface energy of the peripheral edge region is smaller than a surface energy of a remaining region of the two adhesion surfaces and a surface energy of an adhesive used in the adhesion; disposing the display main body and the transparent plate such that the two adhesion surfaces oppose each other via a gap; and injecting the adhesive into the gap.
According to the present invention, the transparent plate can be adhered to the screen of the display main body substantially without applying a load to the screen and the transparent plate. Therefore, damage to the display main body and the transparent plate occurring when the transparent plate is adhered to the screen of the display main body can be prevented.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
The present invention is applied to the manufacture of a flat panel display such as an electron beam display panel, a liquid crystal display panel, an EL display panel, or a plasma display panel, for example. The present invention may also be used to manufacture a cathode ray tube (CRT) display. Further, a display main body according to the present invention refers to a panel part constituting a screen in a flat panel display and a CRT part in a CRT display. The present invention will be described in detail below using manufacture of a flat panel display as an example.
As shown in
As shown in
First, as shown in
As shown in the drawings, the surface treatment is preferably performed on the peripheral edge regions 3b, 3′b of both adhesion surfaces 3a, 3′a to prevent the adhesive 5 from spreading to the outside and ensuring that the adhesive 5 is distributed evenly between the adhesion surfaces 3a, 3′a not subjected to the surface treatment. However, the surface treatment may be performed on only one of the peripheral edge region 3b of the adhesion surface 3a forming the outer surface of the screen of the display main body 1 and the peripheral edge region 3′b of the adhesion surface 3′a forming one surface of the transparent plate 2. Even when the surface treatment is performed on only one of the adhesion surfaces 3a, 3′a, the adhesive 5 can be prevented from spreading to the outside and the adhesive 5 can be distributed evenly between the adhesion surfaces 3a, 3′a not subjected to the surface treatment. Further, the surface treatment performed on the peripheral edge regions 3b, 3′b of the adhesion surfaces 3a, 3′a need not be applied continuously to the peripheral edge regions 3b, 3′b, as shown by the respective regions of the surface treatment agents 3c, 3′c in
The surface treatment is performed by applying the surface treatment agents 3c, 3′c, which are fluorine-based or silicone-based, for example, to the peripheral edge regions 3b, 3′b of the adhesion surface 3a of the display main body 1 and the adhesion surface 3′a of the transparent plate 2. A typical printing method, partial spraying method, inkjet method, or similar may be used as the method of applying the surface treatment agents 3c, 3′c. Further, surface activation treatment such as UV ozone treatment, corona discharge treatment, or plasma discharge treatment is preferably implemented on the peripheral edge regions 3b, 3′b of the adhesion surface 3a of the display main body 1 and the adhesion surface 3′a of the transparent plate 2 before performing the surface treatment. By implementing this surface activation treatment, the adhesiveness of the surface treatment agents 3c, 3′c relative to the peripheral edge regions 3b, 3′b is improved.
Further, the surface treatment agents 3c, 3′c are selected in accordance with the materials of the adhesion surface 3a of the display main body 1 and the adhesion surface 3′a of the transparent plate 2. More specifically, when the adhesion surfaces 3a, 3′a of the display main body 1 and the transparent plate 2 are formed from glass and resin film, a surface energy value thereof is within a range of 40 to 60 dyne/cm. In this case, a surface energy value of the used surface treatment agents 3c, 3′c is preferably within a range of 18 to 31 dyne/cm to prevent the adhesive 5 from spreading and ensure that the adhesive 5 is distributed evenly between the adhesion surfaces 3a, 3′a not subjected to the surface treatment. For similar reasons, the surface energy value of the surface treatment agents 3c, 3′c is even more preferably within a range of 18 to 22 dyne/cm.
Furthermore, the surface treatment is preferably performed within a width range of 1 mm to 3 mm from end portions of the adhesion surfaces 3a, 3′a (end portions of the display plate 10 and the transparent plate 2) inward. By setting this width range, the effects of preventing the adhesive 5 from spreading, ensuring that the adhesive 5 is distributed evenly between the adhesion surfaces 3a, 3′a not subjected to the surface treatment, and improving the shock resistance of the display main body 1 can be obtained more easily. Further, as shown in
Next, as shown in
In this embodiment, the display main body 1 and the transparent plate 2 are disposed such that the adhesion surface 3a of the display main body 1 and the adhesion surface 3′a of the transparent plate 2 are parallel to each other. The adhesion surfaces 3a, 3′a are preferably both vertical but may be tilted.
In a case where the display main body 1 is a main body part of a flat panel display, the display main body 1 and the transparent plate 2 can be disposed opposite each other in the following manner, for example, as shown in
Next, as shown in
A thermosetting adhesive, a cold setting adhesive, a two liquid reactive adhesive, a UV setting adhesive, and so on may be used as the adhesive 5. When the transparent plate 2 is made from a material that transmits UV light, a UV setting adhesive is preferably used. Further, the surface treatment described above is performed such that the surface energy of the peripheral edge regions 3b, 3′b decreases below the surface energy of the adhesive 5 used during adhesion. In other words, the adhesive 5 is selected in accordance with the surface treatment agents 3c, 3′c used during the surface treatment such that the surface energy value thereof is greater than the surface energy value of the surface treatment agents 3c, 3′c. Moreover, as noted above, when glass and resin film are used as the materials of the adhesion surfaces 3a, 3′a, the surface energy value of the used adhesive 5 is preferably within a range of 36 to 47 dyne/cm. By setting the surface energy value within this range, the effects of preventing the adhesive 5 from spreading and ensuring that the adhesive 5 is distributed evenly between the adhesion surfaces 3a, 3′a not subjected to the surface treatment are obtained more easily. Furthermore, to improve the shock resistance of the display main body 1 and ensure that the adhesive 5 is distributed easily and evenly, a viscosity of the adhesive 5 is preferably within a range of 0.05 Pa·s to 10 Pa·s.
Injection may be performed by the dispenser 4 in one or a plurality of locations, but when a plurality of the nozzles 6 are used such that the adhesive 5 is injected from a plurality of locations at the same time, the injected adhesive 5 flows down through the gap in a curtain shape, thereby preventing air bubble entrainment, and therefore this method is preferable. Further, when the adhesive 5 is injected using a slit-form nozzle employed in a slit coater or the like such that the nozzle corresponds to a width of the upper side of the gap between the adhesion surfaces 3a, 3′a, the adhesive 5 can be injected in a smooth curtain shape without air bubble entrainment, and therefore this method is even more preferable. In these cases, the discharge pressure and injection pressure may be set as described above. More specifically, a tip end surface of the injected adhesive 5 sinks downward under its own weight, and therefore the adhesive 5 is preferably injected at a speed that allows replenishment of the injected amount.
The adhesive 5 may be injected by the dispenser 4 until the adhesive 5 has traveled over the entire region between the two adhesion surfaces 3a, 3′a, excluding the peripheral edge regions 3b, 3′b. However, the adhesive 5 is preferably injected in the following manner. Specifically, injection of the adhesive 5 is terminated before the adhesive 5 has traveled over the entire region between the adhesion surfaces 3a, 3′a, excluding the peripheral edge regions 3b, 3′b. The gap between the adhesion surfaces 3a, 3′a is then narrowed using the fine motion stages of the aforesaid holding mechanism. Thus, the adhesive 5 is pressed from either side, and as a result, the adhesive 5 can travel over the entire region between the adhesion surfaces 3a, 3′a, excluding the peripheral edge regions 3b, 3′b.
More preferably, the adhesive 5 is pressed by releasing the display main body 1 and the transparent plate 2 from the holding mechanism and turning the transparent plate 2 to face upward so that the two adhesion surface 3a, 3′a are held in a horizontal state, as shown in
The injected adhesive 5 is typically distributed through the gap concentrically under its own weight, and therefore, when the adhesive 5 reaches the periphery of the adhesion surfaces 3a, 3′a, the adhesive 5 spreads out from this location. In this embodiment, however, the adhesive 5 is flicked back by the surface-treated peripheral edge regions 3b, 3′b of the adhesion surfaces 3a, 3′a during the distribution process, and therefore the adhesive 5 flows so as to fill the parts of the gap that are more easily wetted and as yet unfilled. Hence, the adhesive 5 travels over the entire region between the adhesion surfaces 3a, 3′a not subjected to the surface treatment naturally without spreading. The adhesive 5 is then hardened using a method corresponding to the employed adhesive 5, whereupon the adhesion operation is terminated.
As shown in
Likewise in this embodiment, as described with reference to
The nozzle 6 employed in this embodiment is narrower than the distance of the gap between the two adhesion surfaces 3a, 3′a and is connected to the dispenser 4 for use. The dispenser 4 and the nozzle 6 may be used singly or in pluralities. The adhesive 5 is preferably injected from a plurality of the nozzles 6 at the same time so that the adhesive 5 can be injected into the entire region of the gap on the inner side of the surface-treated peripheral edge regions 3b, 3′b efficiently and quickly. Note that a position of the tip end of the nozzle 6 at the start of the injection process is preferably set on a far side of the gap as seen from the dispenser 4, as shown in
Next, as shown in
The adhesive 5 may be injected by the dispenser 4 such that the adhesive 5 travels over the entire region of the adhesion surfaces 3a, 3′a of the display panel 1 on the inner side of the peripheral edge regions 3b, 3′b subjected to the surface treatment, but similarly to the first embodiment, the adhesive 5 is preferably injected in the following manner. Specifically, injection of the adhesive 5 is terminated before the adhesive 5 has traveled over the entire region between the adhesion surfaces 3a, 3′a, excluding the peripheral edge regions 3b, 3′b, whereupon the gap between the two adhesion surfaces 3a, 3′a is narrowed. Thus, pressure is applied to the adhesive 5, and as a result, the adhesive 5 can be caused to travel over the entire region of the gap between the adhesion surfaces 3a, 3′a, excluding the peripheral edge regions 3b, 3′b.
Further, as described in the first embodiment, the adhesive 5 is preferably pressed by turning the transparent plate 2 to face upward and releasing at least the transparent plate 2 from the holding mechanism. In other words, the pressing force generated by the weight of the transparent plate 2, a natural capillary action, and the surface treatment implemented on the peripheral edge regions 3b, 3′b work together to cause the adhesive 5 to travel favorably without applying excessive pressure.
Once the adhesive 5 has been caused to travel over the entire region of the adhesion surfaces 3a, 3′a on the inner side of the peripheral edge regions 3b, 3′b in this manner, the adhesive 5 is hardened using a method corresponding to the employed adhesive 5, whereupon the adhesion operation is terminated.
A display is manufactured by connecting a driving apparatus to the display main body in which the transparent plate 2 is adhered to the screen, as described in the two embodiments above, and mounting the resulting display main body in a case.
First and second examples will be described on the basis of
First, a face plate was prepared by forming a black light blocking member having a plurality of matrix-form opening portions, a fluorescent body positioned inside each opening portion, and an anode electrode covering a surface of the light blocking member and the fluorescent bodies on one surface of a 700 mm×1240 mm×thickness 2.5 mm soda-lime glass. Further, a rear plate was prepared by forming a plurality of row wirings and a plurality of column wirings, a plurality of field emission type electron-emitting devices connected to the wirings, and a plurality of spacers on one surface of a soda-lime glass of an identical size to the soda-lime glass described above. A glass frame was then attached to the periphery of the aforementioned surface of the rear plate, whereupon a frit glass was disposed on the frame. The face plate and the rear plate were then held in a vacuum atmosphere of 10−6 Pa such that the fluorescent bodies and the electron-emitting devices opposed each other, whereupon heat fusion was applied to the frit glass to join the face plate to the frame. As a result, a panel-shaped display main body 1 having a thickness of 8.0 mm was created.
Next, an anti-static transparent resin film was adhered to the outer surface of the screen of the display main body 1. The transparent resin film is a PET film in which a polyester resin (PET) coating layer through which ITO particles are dispersed is formed on a surface thereof, and the size of the transparent resin film is substantially equal to the size of the display plate constituting the screen of the display main body 1. The PET film was adhered to the outer surface of the screen of the display main body 1 using an acrylic adhesive. In this example, the display plate is constituted by the soda-lime glass forming the face plate and the anti-static transparent resin film, and the adhesion surface 3a of the display main body 1 is the PET coating layer through which ITO particles are dispersed.
Further, a soda-lime glass of an identical size to the display plate 10 of the display main body 1 was prepared, and an anti-reflection transparent resin film was adhered to one surface of the soda-lime glass. An acrylic resin layer through which silica microparticles are dispersed is formed on a PET film surface of the transparent resin film, and the size of the transparent resin film is substantially equal to the size of the soda-lime glass to which it is adhered. The PET film was adhered to the surface of the soda-lime glass using an acrylic adhesive. In this example, the transparent plate 2 is constituted by the soda-lime glass and the anti-reflection transparent resin film. The adhesion surface 3′b of the transparent plate 2 is the aforementioned glass surface.
Next, UV ozone treatment was implemented in a 2.0 mm width region extending inward from the four sides of the display plate forming the adhesion surface 3a of the display main body 1 and a 1.5 mm width region extending from the four sides to the side faces of the display plate. Next, a spraying method was employed to apply an alcohol-diluted solution of trifluoropropyl-trimethoxysilane (KBM-7103, manufactured by Shin-Etsu Silicones) as a surface treatment agent to the peripheral edge region 3b and side faces of the display plate subjected to the UV ozone treatment using a mask, whereupon the solution was dried. Similar treatment was performed on the peripheral edge region 3′b of the adhesion surface 3′a and the side faces of the transparent plate 2. Thus, the surface-treated peripheral edge regions 3b, 3′b and sides faces were formed on the display main body 1 and the transparent plate 2, respectively, as shown in
Next, as shown in
First, a lattice-shaped aluminum jig having a large number of rubber adsorption pads arranged in matrix form on one surface thereof was adsorbed to the rear plate surface of the display main body 1. Meanwhile, a similar jig was adsorbed to the transparent resin film surface of the transparent plate. Then, using a fine motion stage and a length measuring machine connecting the four corners of the two jigs, the gap between the adhesion surface 3a of the display main body 1 and the adhesion surface 3′a of the transparent plate 2 was set at 300 μm.
Next, as shown in
The adhesive 5 was then injected into the gap between the adhesion surfaces 3a, 3′a of the display main body 1 and the transparent plate 2 from the upper side. An injection pressure was not set to be particularly strong at this time, and instead the adhesive 5 was allowed to fall under its own weight. The internal discharge pressure of the dispensers 4 was set at 100 KPa and the injection pressure into the gap was set at 0 KPa. An acrylic UV setting resin adhesive having a composition shown below in Table 1 was used as the adhesive 5. The surface energy of the adhesive 5 was 42 dyne/cm and the viscosity thereof was 800 mPa·s.
Injection of the adhesive 5 by the dispensers 4 was terminated at the point where the tip end of the injected adhesive 5 reached a position 5 mm from a lower side of the display plate and transparent plate 2. The entire holding mechanism was immediately disposed horizontally such that the transparent plate 2 faced upward, whereupon the holding mechanism was removed from the display main body 1 and the transparent plate 2. The display main body 1 and transparent plate 2 were then left in the horizontal state for two minutes to allow the adhesive 5 to travel over the entire region of the gap. Finally, 30 mW/cm2 ultraviolet rays were applied from the transparent plate 2 side for four minutes to harden the adhesive 5, whereby adhesion of the transparent plate 2 to the outer surface of the screen of the display main body 1 was completed. Although the adhesive 5 extended to the peripheral edge regions 3b, 3′b of the two adhesion surfaces 3a, 3′a, no adhesive 5 was observed to have spread so as to smear the sides faces of the display plate on the display main body 1 and the side faces of the transparent plate 2. Moreover, no air bubbles were found in the injection region of the adhesive 5. Note that in this example, a plate material formed from a glass and an anti-reflection transparent resin film was used as the transparent plate, but a single glass plate may be used. In this case, the glass transparent plate 2 is adhered to the display plate surface of the display main body 1, whereupon an anti-reflection transparent resin film is adhered to the surface of the glass transparent plate 2.
Similar surface treatment to that of the first example was implemented on the peripheral edge region 3b of the adhesion surface 3a of the display main body 1 and the side faces of the display plate forming the adhesion surface 3a, but not on the transparent plate 2. Otherwise, the display main body 1 and the transparent plate 2 were adhered to each other in a similar manner to the first example. The adhesive 5 spread slightly, but by wiping the spread adhesive 5 away before hardening the adhesive 5, it was possible to prevent the adhesive 5 from smearing the side faces of the display plate on the display main body 1 and the side faces of the transparent plate 2. Likewise in this example, no air bubbles were found in the injection region of the adhesive 5.
Similar surface treatment to that of the first example was implemented on an identical display main body 1 and an identical transparent plate 2 to the first example, whereupon the display main body 1 and transparent plate 2 were held using a similar holding mechanism to the first example. Note that in this example, the gap between the two adhesion surfaces 3a, 3′a was set at 350 μm. The entire holding mechanism was then disposed such that the transparent plate 2 faced upward and the two adhesion surfaces 3a, 3′a were horizontal.
Next, five apparatuses formed by attaching an SUS304T capillary pipe (manufactured by FUJINO KINZOKU CO., LTD) having an outer diameter of φ300 μm, an inner diameter of φ150 μm and a length of 1000 mm to the dispenser 4 as the nozzle 6 were prepared. The five nozzles 6 were then arranged relative to the 700 mm short side of the gap between the two adhesion surfaces 3a, 3′a in positions of 100 mm, 225 mm, 350 mm, 475 mm and 600 mm from one side. The tip ends of the respective nozzles 6 were then inserted to a position of 950 mm inside the gap from the short side, as shown in
At a point where the position of the adhesive 5 among the nozzles 6 of the dispensers 4 reached a position 10 mm away from the short side, injection was terminated and the nozzles 6 were removed from the gap. The holding mechanism was then immediately released from the display 1 and the transparent plate 2. The display main body 1 and the transparent plate 2 were then left in the horizontal state for two minutes to allow the adhesive 5 to travel over the entire region of the gap. Finally, 30 mW/cm2 ultraviolet rays were applied from the transparent plate 2 side for four minutes to harden the adhesive 5, whereby adhesion of the transparent plate 2 to the outer surface of the screen of the display main body 1 was completed. Although the adhesive 5 extended to the peripheral edge regions 3b, 3′b of the two adhesion surfaces 3a, 3′a, no adhesive 5 was observed to have spread so as to smear the sides faces of the display plate and the side faces of the transparent plate 2. Moreover, no air bubbles were found in the injection region of the adhesive 5.
Similar surface treatment to that of the first example was implemented on the peripheral edge region 3b of the adhesion surface 3a of the display main body 1 and the side faces of the display plate forming the adhesion surface 3a, but not on the transparent plate 2. Otherwise, the display main body 1 and the transparent plate 2 were adhered to each other in a similar manner to the third example. The adhesive 5 spread slightly, but by wiping the spread adhesive 5 away before hardening the adhesive 5, it was possible to prevent the adhesive 5 from smearing the side faces of the display plate on the display main body 1 and the side faces of the transparent plate 2. Likewise in this example, no air bubbles were found in the injection region of the adhesive 5.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2009-241597, filed on Oct. 20, 2009, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-241597 | Oct 2009 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20040241323 | Ylitalo et al. | Dec 2004 | A1 |
| 20070044830 | Uemura | Mar 2007 | A1 |
| 20110007391 | Takahashi | Jan 2011 | A1 |
| Number | Date | Country |
|---|---|---|
| 2000-053453 | Feb 2000 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20110092126 A1 | Apr 2011 | US |
