JP2000200569A - Earth tape and cathode-ray tube by using the earth tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an earth tape having improved connectability to a conductive film and an earthing member, and a cathode-ray tube by using the earth tape. SOLUTION: An earth tape 16 is composed of low melting-point material, and the earth tape 16 is heated and fused in the state to be bridged to a conductive film 14 and an earthing member 15 formed on the outer face of a panel part 1. Hereby, the conductive film 14 and the earthing member 15 can be surely connected electrically by using the earth tape 16 and without using a pressure sensitive adhesive, and conductive connection having stable adhesion can be secured for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth tape for electrically connecting a conductive film formed on a display area to a ground member, and a cathode ray tube using the earth tape.

[0002]

2. Description of the Related Art Generally, a conductive film is formed on an outer surface of a panel portion, which is a display area of a cathode ray tube, for preventing static electricity or preventing a radiation electric field unnecessary for leakage. This kind of conductive film is connected to a conductive member or a low-resistance connecting member (hereinafter referred to as a grounding member) disposed near the panel portion, for example, a protective band which is circulated and grounded near a connection portion between the panel portion and the funnel portion. , Conductive conductive material).

Conventionally, as this kind of conductive connecting material, one using a conductive tape such as a metal foil or the like (see, for example, JP-A-4-174945) and one using ultrasonic soldering (see JP-A-2-75137). JP-A No. 9-205, and a device using a silicone resin containing a conductive filler.
No. 129159) is known.

[0004]

However, in the case of bonding the conductive tape by bridging the conductive film and the grounding member, the tape is peeled off due to the low adhesiveness of the conductive tape such as a metal foil. In addition, there is a problem that the adhesive material is deteriorated and a connection failure is caused.

[0005] Further, there is a problem that complete connection is difficult in the case of connection by ultrasonic soldering.

Further, the use of a silicone resin containing a conductive filler has a problem that the curing time after the application is long and the handling in a subsequent step is not easy.

An object of the present invention is to provide an earth tape which solves the above-mentioned problems of the prior art and has improved connectivity between a conductive film and a ground member, and a cathode ray tube using the earth tape. .

[0008]

In order to achieve the above object, the present invention provides an earth tape made of a low melting point material, and this earth tape is attached to a conductive film formed on an outer surface of a panel portion and a ground member. It is characterized in that it is heated and fused in a bridged state.

The typical configurations of the present invention are as follows. That is, (1) an earth tape for connecting a conductive film formed on a display surface of an image display device to a ground member, wherein the earth tape is made of a conductive low melting point material;
In a state where the ground tape was bridged between the conductive film and the ground member, the ground tape was heated and fused to enable electrical connection therebetween.

(2) The ground tape according to (1) is formed of a low melting polymer material containing a conductive filler.

(3) The ground tape described in (1) is formed of a low melting point polymer material in which a conductive wire is embedded.

(4) The ground tape described in (1) is formed of a low melting point conductive layer and a low melting point polymer material.

With the construction of the earth tape described in the above (1) to (4), the earth tape itself melts and is fused to the conductive film formed on the display surface and the earth member, thereby obtaining a strong connection. Also, peeling and cracking of the ground tape can be prevented. Also,
The contact area is widened and discharge of static electricity to the ground is smooth. In addition, since the resin is cured in a short time after fusion, handling in the subsequent process becomes easy.

(5) A panel portion having a conductive film on the outer surface of the display area and coated with a phosphor on the inner surface, a neck portion for accommodating an electron gun, and a funnel portion connecting the panel portion and the neck portion. A vacuum envelope is configured, and a reinforcing band installed around the connection portion of the panel portion with the funnel portion is provided, and an earth tape for electrically connecting the conductive film and the reinforcing band is provided. Then, the ground tape made of a low melting point material was heated and fused in a state of being bridged between the conductive film and the reinforcing band, thereby electrically connecting them.

In the cathode ray tube having the constitution (5), the electrical connection between the conductive film formed on the outer surface of the panel portion and the protective band is ensured, and peeling and cracking of the earth tape can be prevented. Since the contact area is widened, the static electricity is easily discharged to the ground, and is cured in a short time after fusion, so that handling in the subsequent process is facilitated.

The present invention is applicable not only to a cathode ray tube but also to a liquid crystal panel, a plasma panel, an EL panel, and other various pixel display devices.

It should be noted that the present invention is not limited to the above configuration and the embodiments described later, and various changes can be made without departing from the technical idea of the present invention.

[0018]

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

FIG. 1 is a sectional view of an essential part for explaining a first embodiment of a cathode ray tube using an earth tape according to the present invention.
Reference numeral 1 denotes a panel portion, 3 denotes a funnel portion, 14 denotes a conductive film for preventing antistatic and / or unnecessary radiation electric field, 15 denotes a reinforcing band as a grounding member, 16 denotes an earth tape, and 17 denotes a reinforcing tape.

On the outer surface of the panel section 1 constituting the vacuum envelope of the cathode ray tube, a conductive film 14 for preventing electrification and / or preventing unnecessary radiated electric fields is formed over the periphery of the display area.

The conductive film 14 is made of, for example, (Ag + S
It is composed of an n) layer and a laminated film in which an SiO ₂ layer is formed thereon by spin coating.

A protective band 15 is installed via a protective tape 17 around the joint portion (ie, skirt) of the panel portion 1 with the funnel portion 3. This protective band also functions as a grounding member, and is connected to ground while being mounted on a monitor or a receiver.

The conductive film 14 and the protective band 15
The conductive film 14 is electrically connected to the protective band 15 by bridging the ground tape 16 by bridging therebetween.

According to this embodiment, the ground tape 16 itself melts and is fused to the conductive film 14 formed on the panel portion 1 and the protective band 15 to obtain a strong connection, thereby preventing peeling and cracking of the ground tape. it can. In addition, the contact area is widened, and the discharge of the static electricity to the ground becomes smooth. In addition, since the resin is cured in a short time after fusion, handling in the subsequent process becomes easy.

FIGS. 2A and 2B are explanatory views of a first embodiment of the ground tape according to the present invention, wherein FIG. 2A is a plan view, and FIG. 2B is a sectional view taken along line AA of FIG.

The grounding tape 16 is a rectangular tape and has a low melting point conductive silicon resin 16a or the like, for example, “SE677U” (trade name) manufactured by Toray Dow Silicon Co., Ltd. or a silicon film “silica” manufactured by Mitsubishi Plastics. "(Product name)
And a tape-shaped member formed by mixing particles such as C (carbon), Ag, and Sn as conductive particles 16b as a filler.

As shown in FIG. 1, this ground tape 16 is applied by bridging between the conductive film 14 and the protective band 15 at the corner of the panel portion of the cathode ray tube, and the tube temperature of the cathode ray tube itself is high. It is melted in a state or by heating from the outside with an electric heater or the like, and is fused to the conductive film 14 and the protective band 15 to be electrically connected.

The melting point of the conductive silicon resin having a low melting point constituting the ground tape 16 must be low and must be higher than the operating temperature of the product to be applied, that is, the temperature during use.

In the case of a cathode ray tube, the temperature immediately after firing of the panel portion is about 60 degrees, and the temperature of the panel portion 1 (the temperature of the conductive film 14 and the protective band) is raised by 5 degrees or more. Attach ground tape 16 or ground tape 1
The earth tape 16 is fused by a method of externally heating with a heater in a state where 6 is applied to a predetermined portion.

In any method, a material and a temperature are selected so that the viscosity when melted becomes 10 Pa or more so that the ground tape 16 does not flow down when the melting point is reached.

By adjusting the material, shape, size and amount of the filler, it is possible to obtain any desired conductivity, melting point, strength and adhesion.

FIGS. 3A and 3B are explanatory views of a second embodiment of the earth tape according to the present invention, wherein FIG. 3A is a plan view, and FIG. 3B is a sectional view taken along line BB of FIG.

The ground tape 16 'is also a rectangular tape, and is formed by molding a low melting point conductive wire 19 on a silicon film similar to that shown in FIG. Shaped member.

As shown in FIG. 1, the ground tape 16 'is applied to the conductive film 14 at the corner of the panel of the cathode ray tube.
And the protective band 15 are attached by bridging, and the cathode ray tube itself is melted by heating with an electric heater or the like in a state where the tube temperature is high as in the case of FIG.
The conductive film 14 and the protective band 15 are fused and electrically connected.

The cross-section of the low-melting conductive wire 19 to be molded does not need to be circular as shown in the figure, and the material is, for example, low-melting solder, which is equivalent to the low-melting conductive silicon resin 18. Any material having a melting point may be used.

Further, when a material having high adhesiveness to the conductive film or the protective band is used as a constituent material of the ground tape, it is more preferable that the wire 19 to be molded is partially exposed on the surface of the silicon resin 18. High conductivity can be obtained.

The melting point of the low melting point conductive silicon resin or the like constituting the ground tape 16 is low and needs to be higher than the operating temperature of the product to be applied, that is, the temperature at the time of use. The same is true.

FIG. 4 is a sectional view showing a main part of a cathode ray tube using an earth tape according to a second embodiment of the present invention.
The same reference numerals as those in FIG. 1 correspond to the same parts, 16 "denotes a ground tape, 20 denotes a low melting point solder sheet, and 21 denotes a low melting point silicone resin.

In the present embodiment, a grounding tape 16 ″ is fused between the conductive film 14 formed on the panel portion 1 and the protective band 15 so that the conductive film 14 is bonded to the protective band 15.
Is electrically connected to

FIG. 5 is an explanatory view of a third embodiment of the earth tape of the present invention. FIG. 5 shows an example of the structure of the earth tape used in FIG. 4, wherein (a) is a plan view and (b) is ( a) C-
FIG. 4 shows a cross-sectional view along line C.

The ground tape 16 ″ is obtained by laminating a low-melting-point silicone resin 21 on a part of one surface of a low-melting-point solder sheet 20. 21 is brought into close contact with the conductive film 14 and melted in the same heating state as in the above embodiment to make an electrical connection.In FIG. , Arrows EE indicate the protective band 15
Shows the part to be fused.

The low melting point solder sheet 20 has good adhesion when the protective band 15 is made of iron, and the low melting point silicon resin 21 has a conductive film 1 having silicon dioxide as an upper layer.
4 and good adhesion.

Although the area of the low melting point solder sheet 20 is larger than that of the low melting point silicon resin 21 in FIG. 5, the magnitude relation is not limited to this as long as the electrical conductivity is good.

Although the low melting point solder sheet 20 and the low melting point silicon resin 21 have a laminated structure formed integrally, they may be attached as separate sheets. However, since the number of steps increases accordingly, it is desirable to use an integrated one.

According to this embodiment, the earth tape 1
Conductive film 1 formed on panel portion 1 by melting 6 ″ itself
4 and the protective band 15 are fused to obtain a strong connection, and peeling and cracking of the ground tape can be prevented. In addition, the contact area is widened, and the discharge of the static electricity to the ground becomes smooth.
In addition, since the resin is cured in a short time after fusion, handling in the subsequent process becomes easy.

As a material for the above-mentioned earth tape, a low melting point resin such as a polyvinyl chloride resin, a polyvinyl alcohol resin, a polyethylene resin or a polyamide resin may be used instead of the low melting point silicone resin. It is possible to mix these resins with carbon to adjust the conductivity and the coefficient of thermal expansion before use.

Next, the step of fusing the earth tape to the cathode ray tube will be briefly described.

FIG. 6 is an explanatory view of a step of fusing an earth tape to a cathode ray tube. The cathode ray tube is baked in a baking furnace 30 through processes such as vacuum sealing and mounting of a protective band, and formation of a conductive film on a panel portion.

The cathode ray tube that has exited the firing furnace 30 is transferred to a conveyor 31 as shown by an arrow a, and is conveyed to an earth tape attaching and heating device 32 as shown by an arrow b. Since the temperature of the panel portion of the cathode ray tube when exiting the firing furnace 30 is 60 ° C. or more, the cathode ray tube is transported in the layout shown in the drawing, and the cathode ray tube panel is attached at the time when the cathode ray tube is attached to the heating device 32. The temperature of the part will be about 60 degrees.

The cathode ray tube to which the earth tape has been applied and the earth tape has been fused by the heating device 32 is conveyed as indicated by an arrow c, and sent to the next inspection step.

FIG. 7 is an explanatory view of a state in which the cathode ray tube is transported on the production line. The cathode ray tube is placed on a pallet 31a and transported on the free flow chain conveyor 31.
The pallet 31a has a holding member 31b for receiving a bracket 15a fixed to the protection band 15 on the upper surface of a substantially rectangular frame.

The free flow chain conveyor 31 has a free flow chain 33, on which a pallet 31a loaded with cathode ray tubes is moved. The transport of the cathode ray tube is not limited to the illustrated one, and other general known cathode ray tube transport methods can be adopted.

FIG. 8 is a front view of the pallet, illustrating the step of applying and bonding the ground tape in the ground tape and the heating device, as viewed from the traveling direction of the pallet. The earth tape attaching and heating device is provided with an earth tape attaching device (not shown) and a heating device 32a.

The earth tape 16 stuck by the earth tape sticking device is heated and fused by the heating device 32a. As the heating device 32a, a high-frequency heating device, an infrared heater, a hot air blower, or the like is used.

With this configuration, the fusion of the ground tape to the cathode ray tube can be automatically performed.

FIG. 9 is a schematic sectional view of a shadow mask type color cathode ray tube for explaining an example of the structure of the cathode ray tube according to the present invention. The panel 1, the neck 2 and the funnel 3 constitute a vacuum envelope, and the protective band 15 is tightened near the junction between the panel 1 and the funnel 3.

The phosphor 4 is applied to the inner surface of the panel unit 1, and the conductive film 14 is formed on the outer surface. A shadow mask 5, which is a color selection electrode, is supported by the mask frame 6 and suspended on the inner wall of the skirt of the panel unit 1 by a suspension mechanism 8 in proximity to the phosphor 4. A magnetic shield 7 is attached to the mask frame 6.

An in-line type electron gun 9 is housed in the neck portion 2, and a stem pin 12 penetrates to the outside from the edge. A magnetic device 11 for static convergence and color purity adjustment is provided outside the neck portion 2.

A deflection yoke 10 is provided in the transition region of the funnel portion 3 to the neck portion 2, and an electron beam B (center beam, side beam × 2) emitted from the electron gun 9 is provided.
Is deflected horizontally and vertically to make the screen composed of the phosphor 4 2
A required image is reproduced by scanning in a dimension.

The conductive film 14 for preventing static electricity and / or unnecessary radiated electric field formed on the outer surface of the panel portion 1 and the protective band 15 are electrically connected by welding a ground tape 16.

With the color cathode ray tube having this configuration, the conductive film 14 is reliably grounded, and a good color image can always be reproduced without peeling or tearing of the ground tape over time.

[0062]

As described above, according to the present invention,
In a display device such as a cathode ray tube having a conductive film formed on or around the display area and having a grounding member for grounding the conductive film, an adhesive is used between the conductive film and the grounding member using a ground tape. It is possible to reliably and electrically connect without any trouble, and it is possible to secure a conductive connection with stable adhesion over a long period of time.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a first embodiment of a cathode ray tube using an earth tape according to the present invention.

FIG. 2 is an explanatory view of a first embodiment of the ground tape according to the present invention.

FIG. 3 is an explanatory view of a second embodiment of the ground tape according to the present invention.

FIG. 4 is a sectional view showing a main part of a cathode ray tube using a ground tape according to a second embodiment of the present invention.

FIG. 5 is an explanatory view of a third embodiment of the ground tape of the present invention.

FIG. 6 is an explanatory view of a step of fusing an earth tape to a cathode ray tube.

FIG. 7 is an explanatory diagram of a state in which a cathode ray tube is transported on a production line.

FIG. 8 is a front view illustrating a step of applying and bonding a ground tape in a ground tape and a heating device, as viewed from a traveling direction of a pallet.

FIG. 9 is a schematic sectional view of a shadow mask type color cathode ray tube for explaining an example of the structure of the cathode ray tube according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel part 3 Funnel part 14 Conductive film 15 Protective band 16 Earth tape 17 Protective tape.

Claims (2)

[Claims] 1. A grounding tape for connecting a conductive film formed on a display surface of an image display device to a grounding member, wherein the grounding tape is made of a conductive low melting point material, and An earth tape, wherein the tape is heated and fused in a state where the tape is bridged between the conductive film and the grounding member, so that the two can be electrically connected. 2. A vacuum is formed by a panel portion having a conductive film on the outer surface of the display area and applying a phosphor on the inner surface, a neck portion for accommodating an electron gun, and a funnel portion connecting the panel portion and the neck portion. An enclosure is provided, comprising: a reinforcing band installed around the connection portion of the panel portion with the funnel portion; and an earth tape for electrically connecting the conductive film and the reinforcing band. Wherein the ground tape is made of a low-melting-point material, and the two are electrically connected by heating and fusion in a state of being bridged to the conductive film and the reinforcing band. And a cathode ray tube.