JPH04345731A - Dust removing method for cathode-ray tube bulb - Google Patents

Abstract

PURPOSE:To prevent the deterioration of withstand voltage by putting the fine pieces or granules, of an easily electrified member and a magnetized member, in the inner side of a bulb or a bulb structure to be vibrated or rotated, and eliminating an adherent substance sticked on the inner side of the bulb or the structure by the friction of the vibration or rotation. CONSTITUTION:Fine pieces or granules of an easily electrified member are put in the inner side of a glass-made bulb structure such as a panel and a funnel of a black-and-white picture tube or a color picture tube just arrived. Then the inner surface of the bulb or the structure is rubbed with these fine pieces or granules by vibrating the bulb or the bulb structure or suitably tilting them to be rotated. In this case, a substance, easily electrified of static electricity, having low hardness, and containing no halogenation element such as Cu, F, and Cl, like formal resin and acrylic resin etc., is used as the easily electrified member. One end opening such as the bulb is closed, and then the bulb or the structure is washed with flowing water or hydrofluoric acid water etc., or by a pure-water shower or a supersonic wave.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing dust from cathode ray tube bulbs.

0003

[Prior Art] In general, cathode ray tubes and color picture tubes have a phosphor screen formed on the inner surface of a glass panel, this panel is integrally joined with a glass funnel, and then an electron gun is sealed inside the neck of the funnel. It is produced by evacuation. In addition, for industrial Braun lights such as black and white picture tubes and oscilloscopes, a glass face plate and a glass cone are welded together, and a fluorescent screen is formed on the inner surface of the face plate of the glass bulb. It is manufactured by sealing an electron gun inside the neck and evacuating it.

Normally, these color picture tube panels, valve components such as funnels, black and white picture tubes, and industrial Braun bulbs are manufactured by specialized manufacturers (abbreviated as valve specialty manufacturers), packaged in cardboard boxes, etc., and shipped to cathode ray tubes. Supplied to manufacturers. At this point, these valves and valve components have fibrous materials such as paper scraps and thread scraps, slag from press molding, iron scraps, and the like adhering to them. Therefore, in order to remove these deposits, cathode ray tube manufacturers first remove them by cleaning with running water, hydrofluoric acid, etc., or by air blowing.

[0005] However, some of the above-mentioned deposits include those that are firmly attached due to cleaning and drying at a manufacturer specializing in valves, and those that are attached due to mold release agents and static electricity during press molding. Therefore, it is difficult to completely remove the deposits by the above-mentioned cleaning, air blowing, etc. Therefore, the residual deposits may cause defects in the phosphor screen that is subsequently formed on the inner surface of the panel or face plate, may adhere to other parts and block the electron beam emitted from the electron gun, or may cause spark discharge or stray particles. This causes problems such as generation of emissions and deterioration of withstand voltage.

[0006] In particular, for valves in which the face plate and cone are integrated, which are used for monochrome picture tubes and industrial Braun cameras, sufficient cleaning effects cannot be obtained by the above-mentioned cleaning or air blowing, so friction with a brush is also used for cleaning. Kimono is removed.

However, in this cleaning method, the brush does not reach the required areas, and brush debris is likely to be generated. Even when cleaning with hydrofluoric acid water, there are problems such as residual hydrofluoric acid residue, uneven treatment caused by the hydrofluoric acid, and the need to control the hydrofluoric acid concentration.

[0008]

[Problems to be Solved by the Invention] As mentioned above, the panels of color picture tubes, bulb components such as funnels, black and white picture tubes, and industrial brown bulbs must first be cleaned with running water, hydrofluoric acid water, etc., or with air blowing. Used after processing. However, among the deposits on the valves and valve components mentioned above, there are deposits that are relatively easy to remove, such as paper waste and thread waste, as well as deposits that have firmly adhered due to cleaning and drying at a manufacturer specializing in valves, and deposits that have adhered during press molding. Since many substances are strongly adhered, such as mold release agents and substances adhered by static electricity, it is difficult to completely remove the adhered substances by the above-mentioned cleaning or air blowing, and the remaining adhered substances are then removed from the panel. It can damage the phosphor screen formed on the inner surface of the face plate, it can adhere to other parts and block the electron beam emitted from the electron gun, or it can cause spark discharge or stray emissions, deteriorating the withstand voltage. This causes problems such as In particular, for bulbs used in black-and-white picture tubes and industrial Brauns, sufficient cleaning effects cannot be obtained with the above-mentioned cleaning or air blowing, so friction with a brush is also used. Brush debris is likely to be generated. Even when cleaning with hydrofluoric acid water, there are problems such as residual hydrofluoric acid residue, uneven treatment caused by the hydrofluoric acid, and the need to control the hydrofluoric acid concentration.

The present invention has been made in view of the above-mentioned problems, and is intended to easily remove deposits that adhere firmly to color picture tube panels, bulb components such as funnels, and black and white picture tubes and industrial brown bulbs. It is an object of the present invention to provide a dust removal method that can remove dust sufficiently.

[Configuration of the invention]

[0011]

[Means for Solving the Problems] In a cathode ray tube bulb dust removal method for removing deposits adhering to the inner surface of a cathode ray tube bulb or valve component, a member that is easily charged or a magnetized member is Small pieces or granules or a mixture of small pieces or granules of these members are put in and vibrated or rotated, and the electrification of the easily charged member or the magnetism of the magnetized member obtained by the vibration or rotation, and the valve or valve configuration. Friction between the material and the small pieces or granules of the member removes deposits on the inner surface of the valve or valve component.

0012

[Function] As mentioned above, when a small piece or granular material of a member that is easily charged or a magnetized member, or a mixture of small pieces or granular materials of these members is placed and vibrated or rotated, the member that is easily charged becomes electrified due to this vibration or rotation. However, due to the charging of the easily charged member or the magnetism of the magnetized member, and the friction between the valve or valve components and the small pieces or granules of the easily charged member or magnetized member, the inner surface of the valve or valve components is Adhering substances can be easily and sufficiently removed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments with reference to the drawings.

As shown in FIG. 1, glass bulb components such as glass bulbs in which the face plate and cone of incoming monochrome picture tubes or industrial cathode ray tubes are welded together, panels of color picture tubes, funnels, etc. Place small pieces or granules of materials that are easily charged inside. Then, the valve or valve component is rotated with vibration or a moderate inclination, and the inner surface of the valve or valve component is rubbed with these small pieces or particles.

[0015] The above-mentioned materials that are easily charged include formal resins, acrylic resins, etc. that are easily charged with static electricity due to friction, have lower hardness than the valve or valve components, and contain halogen elements such as copper, F, and Cl. What is missing is used.

[0016] In the case of a member having openings at both ends, such as the funnel of a color picture tube, it is necessary to close one end of the opening when a member that is easily charged is inserted and vibrated or rotated.

[0017] Next, after removing the small pieces or granules of the member that is easily charged, the valve and the valve components are appropriately washed with running water, hydrofluoric acid water, etc., and dried. On the other hand, small pieces or granules of easily charged parts taken out from valves or valve components are dried after being subjected to a pure water shower or ultrasonic cleaning. Eliminate static electricity and play.

By the way, before cleaning the valve or valve components as described above, if a small piece or granular material that is easily charged is inserted and vibrated or rotated, the small piece or granular material becomes electrically charged due to friction and gradually becomes electrified. By increasing the electric charge, the static electricity generated by the charge becomes higher than the deposits attached to the valve or valve components, and the deposits whose adhesion force has decreased or have peeled off due to friction with these small pieces or granules are attracted and adsorbed. As a result, deposits that are difficult to remove by conventional cleaning can be easily and sufficiently removed.

As an example, Table 1 shows the results of putting a small piece of Bakelite about 10 mm square into the bulb of a 7-inch projection cathode ray tube, rotating it while tilting it to remove dust, and then washing it with water. Compare and show.

“Table 1”
Example method Conventional method Incoming valve A
37.5 pieces/piece 40.1 pieces/piece After treatment B
8.3 pieces/piece 22
．． 8 pieces/book
(Including thread waste 1.7 pieces/piece) (Including thread waste 9.
7 pieces/piece) Reduction rate (A-B)/A
77.7%
43.1% Table 1 shows the average number of dust particles with a size of 10 μm or more that fell due to tapping for each of the three valves. As can be seen from Table 1, the method of this embodiment can significantly remove deposits that were difficult to remove in the past. It is also shown that the method of this example can effectively remove fibrous substances.

Moreover, according to this dust removal method, small pieces or granular materials of easily charged members used for dust removal can be recycled and reused, and dust can be removed with almost no effect on the manufacturing cost of the cathode ray tube.

[0022] In the above embodiment, dust removal from incoming valves and valve components was described, but regarding the funnel, a conductive paint containing carbon or graphite as a main component is applied to the inner surface of the funnel during the manufacturing process of color picture tubes. Since an internal conductive film is formed using the color picture tube, fine particles of this conductive film are likely to fall off after manufacturing the color picture tube and cause defects. Therefore, if the above-mentioned dust removal method is applied after forming the internal conductive film, the fine particles that easily fall off can be forcibly removed, and the occurrence of defects after manufacturing the color picture tube can be significantly reduced.

Regarding color picture tubes, a shadow mask is assembled into a panel in a predetermined relationship to assemble a panel/mask assembly, and this panel/mask assembly is heated to a high temperature to remove distortion caused by assembly. After stabilizing, a phosphor screen is formed on the inner surface of the panel, but the stabilizing process causes a large amount of iron rust and iron burrs to adhere to the panel. For the removal of such magnetic substances, small pieces or granules of magnetized members such as magnetic rubber are effective, and by using this magnetized member alone or in a mixture with a member that is easily charged, the above-mentioned magnetic substances and Other deposits can be significantly removed. Further, as in the above embodiment, small pieces or granules of the magnetized member, or a mixture with a member that is easily charged can be recycled and used.

[0024]

Effects of the Invention: When a member that is easily charged, a magnetized member, or a mixture of these members is placed inside a cathode ray tube bulb or a valve component and is vibrated or rotated, the small pieces or granules of the member that is easily charged are charged. Adhesion to the inner surface of the valve or valve component due to the charging of the easily charged member or the magnetism of the magnetized member and the friction between the valve or valve component and the small pieces or granules of the easily charged member or magnetized member. It is possible to easily and sufficiently remove the deposits that are attached to the surface.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the invention.

Claims (1)

[Claims] Claim 1: Small pieces or granules of a member that is easily charged or a magnetized member, or a mixture of small pieces or granules of these members are placed inside a cathode ray tube bulb or a valve component, and the vibration or rotation causes The deposits on the inner surface of the valve or valve component are removed by the resulting electrification of the easily charged member or the magnetism of the magnetized member and the friction between the valve or valve component and the small pieces or granules of the member. A method for removing dust from a cathode ray tube bulb.