JPS587018B2 - Ink Yokusenkan - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cathode ray tube, and more particularly to a cathode ray tube having an explosion-proof construction in which a protective panel is bonded to the front face of the cathode ray tube.

Cathode ray tubes, such as television picture tubes, are maintained at a high vacuum inside the tube, so if the tube body is damaged, an implosion accident may occur.

Therefore, an explosion-proof type cathode ray tube is provided by attaching a protective panel made of transparent glass with adhesive to the front of the face plate of the cathode ray tube, which is most likely to be touched by other objects and may be damaged. It was done.

In addition, in a cathode ray tube, for example, 20KV is applied to the fluorescent surface side.
Since a high voltage or even higher voltage is applied, the face plate becomes electrically charged, and if the face plate is touched by a human body, such as a hand, not only during use but also immediately after use, the face plate may receive an electric shock.

This charging occurs even when the above-mentioned protective panel is provided.

In order to prevent charging in a cathode ray tube having the above-mentioned protective panel, the adhesive used to bond the protective panel has a certain degree of conductivity and is grounded.

That is, for example, it is electrically coupled to the chassis of a television receiver.

With this configuration, it is possible to release the electric charge on the front surface of the face plate to the chassis, thereby achieving the effect of sufficiently lowering the electric potential.Furthermore, it is possible to obtain the effect of sufficiently lowering the electric potential of the front surface of the face plate.Moreover, even if the chassis is connected to the commercial power supply voltage, for example, as in a receiver with a transformerless configuration, Even in such cases, the presence of an insulating protective panel can also avoid the risk of electric shock.

The present invention aims to provide a cathode ray tube in which the required conductivity, or in other words, electrical resistance, can be imparted to the front surface of the face plate, and in which a protective panel is firmly adhered. It is something.

An example of the present invention will be described with reference to FIG. 1. In the figure, 1 shows the cathode ray tube as a whole, 2 is the funnel part,
Reference numeral 3 denotes a panel section joined to this funnel section, and this panel section 3 has a face plate 4 having a fluorescent surface on its inner surface.
and a skirt 5 extending toward the funnel portion 2 around it.
and has.

An explosion-proof metal ring 6 is provided on the outer periphery of this skirt 5.
Allocate.

The explosion-proof metal ring 6 may be formed by, for example, wrapping a metal band around it and tightening it, or fitting an annular metal shell and filling the space between this shell and the outer peripheral surface of the skirt 5 with adhesive resin and tightening it. being done.

In the present invention, a protective panel 8 made of, for example, a transparent glass plate is placed opposite to the front surface of the face plate 4 of the panel portion 3 of the cathode ray tube 1 with a required spacing therebetween, and the space between the panel 8 and the face plate 4 is For example, a base agent A made of an unsaturated polyester resin to which a curing accelerator has been added, a glycol solution B in which a metal soap is dissolved, and a curing catalyst C.
The panel 8 is fixed to the face plate 4 by the cured conductive resin layer 7.

Then, the conductive resin layer 7 and the explosion-proof metal ring 6 are electrically connected, and the ring 6 is grounded, or a metal piece (not shown) is brought into contact with the conductive resin layer 7 through the metal piece. and ground.

As the base material A constituting the resin material, for example, Ricolac F-73MB (unsaturated polyester resin to which a curing accelerator has been added; trade name manufactured by Showa Kobunshi ■) may be used.

Further, the solvent B as an additive is, for example, a potassium salt or a sodium salt of each fatty acid such as cabric acid, propionic acid, oleic acid, lauric acid, or both, for example, ethylene glycol, diethylene glycol, triethylene glycol, etc. A solution dissolved in glycols can be used.

Similarly, as the curing catalyst C as an additive, for example, methyl ethyl ketone peroxide can be used.

In addition, in this 5, the blending ratio (weight) of base agent A and solution B is 1.
00 parts: It is desirable to select from 0.05 to 10 parts.

This is based on 100 parts of base agent A and 0 parts of additive B.
．． If the amount is less than 0.5 parts, the resulting resin layer 7 may have insufficient conductivity, and if it exceeds 10 parts, the transparency may decrease or the hygroscopicity may become significant.

Example base agent A: Rigorac F-73MB 100 parts Solution B
: 10% triethylene glycol solution of potassium laurate 5.25 parts Curing catalyst C: Methyl ethyl ketone peroxide
Prepare a resin material by thoroughly stirring and mixing 0.25 parts.

On the other hand, a protective panel 8 made of transparent glass is placed opposite to the front surface of the face plate 4 with an interval of 1 to 3 mm, and its periphery is sealed with, for example, polyester tape, except for the part that will serve as the injection port for injecting the resin. The space between the panel 8 and the face plate 4 is filled with the resin material from the injection port.

Thereafter, this resin material is cured to form the resin layer 7.

This curing can be done by leaving it at room temperature overnight, or for example, by leaving it in a curing oven at about 80°C.
A time curing treatment may also be performed.

Then, a metal piece is brought into contact with the resin layer 7 thus obtained and grounded.

According to the cathode ray tube according to this example, when the power switch is turned on on the surface of the face plate, several KV to IO are generated almost simultaneously.
Although a high voltage of KV was generated, the voltage dropped to below IKV after a few seconds, and even when the surface of the protective panel 8 was touched, no shock due to static electricity or the like was felt.

In contrast, with ordinary cathode ray tubes, the voltage on the surface remains constant even after several tens of minutes to an hour have passed after the power switch is turned on.
It never went below KV.

Furthermore, when the power switch is turned off, the cathode ray tube according to the present invention drops to 100V or less within 30 seconds after being turned off, but a normal tube shows a static voltage of 1 to 2 KV even after several minutes after being turned off, and remains for an hour. Later on, the voltage only dropped to about 400V.

This is because the resin layer 7 of the cathode ray tube according to the present invention has a certain degree of conductivity.

Note that this conductivity can be set by the amount of additive B added, and its resistivity is approximately 5 x 106 ΩCm ~ 5X
It can be set within the range of 109Ωcm.

In FIG. 2, curves 21, 22, 23, and 24 use additive solution B in which potassium laurate is dissolved in a triethylene glycol solution, and the potassium laurate and triethylene glycol are mixed in a weight ratio of 1:5, respectively. 1:7, 1:9,
This is a measurement curve obtained by measuring the resistivity ρ with respect to the total amount (ratio) of each potassium laurate added to the resin when the blending ratio was 1:11.

As described above, in the cathode ray tube according to the present invention, conductivity can be imparted to the resin layer 7 that adheres the protective panel 8 to the face plate 4 of the cathode ray tube, and its transparency is high.
It is possible to avoid the dangers caused by static electricity, etc. without degrading the image quality, so it is useful for practical use.

In particular, since a glycol solution with good solubility for unsaturated polyester resin and metal soap is used, the metal soap can be sufficiently dissolved in the unsaturated polyester resin to obtain the required resistivity without causing so-called turbidity. The amount of addition can be easily controlled, and a transparent conductive cured resin layer can be obtained.

In the present invention, the resin material constituting the resin layer 7 is composed of at least the main resin A, the solution B as an additive, and the curing catalyst C, but in some cases, water may also be added. An appropriate amount of can also be added, and when doing so, the resistance can be further reduced.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a part of an example of a cathode ray tube according to the present invention, and FIG. 2 is a measurement curve of the amount of additive B added to the resin material and the resistivity. 1 is a cathode ray tube, 2 is a funnel part, 3 is a panel part, 4 is its face plate, 5 is a skirt, 7 is a resin layer, 8
is a protective panel.

Claims (1)

[Claims] 1 A protective panel is bonded to the front surface of the face plate of a cathode ray tube via a conductive resin material made of a mixture of unsaturated polyester resin, a glycol solution containing metal soap, and a curing catalyst. A cathode ray tube featuring