JPS61118931A - Cathode-ray tube manufacturing method - Google Patents

Abstract

PURPOSE:To prevent glaring effectively and strengthen the adhesion power of membrane to bear a long period of use, b applying an electrostatic air blow over the front panel after removing the abrasive and before a specific alcohol solution is sprayed. CONSTITUTION:After the surface of a CRT front panel is polished with an abrasive,a nd the abrasive is wiped out by a bleached cloth, an electrostatic air blow is applied, and then the panel surface is preheated. After that, the electrostatic air blow is applied again, and an alcohol solution of (SiOR)4 is sprayed. As a result, when the sprayed particles reach the panel surface, they lose movability and stay on the sprayed surface in globular particles or flat pieces to make up a continued uneven coarse surface, which is later combined with the glass surface by heating and drying at a given temperature. In such a way, antiglaring effect is increased and the membrane adhesion is strengthened.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a cathode ray tube, in particular, in order to prevent the image from becoming difficult to read due to external light specularly reflected on the front panel surface, transparent fine irregularities made of % SiO2 are formed. The present invention relates to a method for producing a plastic tube which is coated with a coating film to diffusely reflect external light and provide an anti-glare effect.

[Background of the invention]

Generally, cathode ray tubes have a glossy panel surface, which tends to strongly reflect external light, making it difficult to read images displayed on the panel surface. As a solution to this problem, a cathode ray tube has been proposed in which a non-glare treatment is applied to the panel surface to diffusely reflect external light. Various methods have been proposed in the past as means for forming diffuse reflection on the surface of a panel. For example, there is a method of selectively etching the glass on the surface of a cathode ray tube panel with hydrofluoric acid to create irregularities. This method has been put into practical use to some extent by sufficiently controlling the conditions, but it is prone to pollution problems, is easily scratched, cannot be reprocessed, and cannot be used as a finished ball. There are many problems such as things that can't be processed. Next, there is a method called sandblasting, in which unevenness is formed on the panel surface by spraying an abrasive. This method has many problems, such as not being able to obtain a certain quality, being unable to recycle, and the risk of contamination with foreign substances such as abrasives.Another method is to coat a plastic film, but It has many drawbacks, such as its surface being easily scratched and being easily eluted by organic solvents.

In addition, as disclosed in Japanese Utility Model Publication No. 44-11150, an uneven coating is formed on the surface by spraying an aqueous solution of an alkali salt of silicic acid (also known as water glass) onto the surface of a cathode ray tube panel and heat-treating the surface. There is also a way to form. However, this method has the problem that because the alkali is contained, it reacts with moisture in the air and becomes cloudy or the surface is eluted.゛Also,
As disclosed in Japanese Utility Model Publication No. 50-26277, by spraying a mixed solution of silicon tetrachloride and alcohols or esters on the surface of a cathode ray tube panel,
A method of forming a film with fine irregularities that may cause damage or
There are many problems with equipment, liquid handling, etc. in the manufacturing process. Furthermore, since halogen ions such as hydrochloric acid are directly linked to the emission slump that is the lifeblood of a cathode ray tube, a process for thoroughly removing the residual components is required, which increases the number of steps and increases production costs.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and its purpose is to provide a method for manufacturing a cathode ray tube equipped with an SiOs antireflection coating that has a good anti-glare effect and also has high adhesive strength. It is in.

[Summary of the invention]

In order to achieve such an object, the present invention spray-coats an alcoholic solution of Si alkoxide, that is, Si(OR)+ (R is an aryal group) to form a Si alkoxide.

The surface of the front panel is sprayed with a alcohol solution that forms a transparent film with fine irregularities.
It is designed to apply electrostatic air blow to the drunken face.

The mechanism by which electrostatic air blow increases the adhesive strength between the panel glass surface and the coating is not necessarily clear, but when rubbed with an abrasive and a bleached cloth, the static electricity charged on the panel glass surface is reduced by electrostatic air blow. This is thought to be due to the fact that it is removed by In other words, if the surface is charged, the polarity will be reversed on the surface as shown in Figure 1 (a), and the ionic bond (hydrogen bond) between the liquid and the glass component will not be formed correctly during spraying. If not, as shown by the broken line in Figure To), this bonding is performed correctly and the adhesive strength is improved.

[Implementation sequence of the invention]

FIG. 2 is a process diagram showing an embodiment of the present invention.

In the figure, the surface of the front panel of the cathode ray tube is first polished with an abrasive (cerium oxide, etc. used for gloss polishing), and after removing the abrasive with a bleaching cloth, an electrostatic air blow is performed and the panel is polished. Preheat the surface to a temperature of 40-100°C. After that, perform electrostatic air blow again,
Spray the alcohol solution of (S i OR)4. When the sprayed particles reach the bare surface of the panel, they lose their fluidity and become granular, spherical or flat, and are fixed on the painted surface to form a continuous uneven surface.
The stone is bonded to the glass surface by heating and drying for 30 minutes.

For example, the electrostatic air blower is manufactured by Simco Japan KKfiFB.
- Static electricity was removed from the base surface for about 1 minute using a power unit.

In the above-mentioned implementation series, electrostatic air blowing was performed once immediately after removing the abrasive and before preheating, and electrostatic air blowing was performed again after preheating and immediately before spraying, but one of them was omitted.
Almost the same effect can be obtained even if the process is performed as shown in FIG. 3 or 4.

When we examined the adhesive strength of the 5-ins film formed in this way and the 5-ins film formed without electrostatic air blowing by rubbing it with an eraser (Lion 5O-50), we found that the method without electrostatic air blowing Because 5L (OR) 4 was sprayed onto the surface of the panel glass, which had a tinge of color, the adhesion of the lath to the base glass was not perfect when the firing temperature was below 150°C, and the film peeled off after 100 to 200 rubbings. On the other hand, with the coating according to the present invention, since the static electricity is completely removed by electrostatic air blowing,
Adhesion between the glass and the film was sufficiently and stably obtained, even when the ashes were burned at 0° C. or lower, and adhesive strength sufficiently large for practical use was obtained without peeling even after rubbing 300 times or more.

In addition, 5i (h coating 4. For the purpose of preventing reflection, it is applied so as to cover at least the effective surface of the front panel, but the surface to be applied may be the inner surface, the outer surface, or both. As for the method of coating the inner surface, it cannot be applied when the cathode ray tube is completed, so it has to be assembled into the cathode ray tube that has been coated when it is a component. There is a tendency for parts to be damaged due to physical and chemical treatments, and the use of parts tends to increase.Therefore, they are usually deposited on external surfaces.

〔Effect of the invention〕

As explained above, according to the present invention, by applying electrostatic air blow to the surface of the front panel after removing the abrasive and before spraying the alcohol solution of Si (OR) 4, a sufficient anti-glare effect can be obtained. Moreover, it is possible to obtain an excellent 5iOz antireflection coating that has a high film adhesion strength and can withstand long-term use without fear of damage to the coating surface during use.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the action of electrostatic air blowing according to the present invention, FIG. 2 is a process diagram showing one embodiment of the present invention, and FIGS. 3 and 4 are diagrams showing other embodiments of the present invention, respectively. It is a process diagram showing a row. Agent Patent Attorney Akira Takahashi 'husband ~, Figure 1 5i-0-5i-〇 - ■θ η゛F人H -Q-5i-0- 5i-〇 -5i -0- -0-5i -0- Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A method for manufacturing a cathode ray tube that has an anti-glare effect by forming a transparent film having fine irregularities made of SiO_2 on the surface of the front panel includes a step of polishing at least one of the inner and outer surfaces of the front panel, and a step of polishing the polished surface. The process of applying electrostatic air blowing and the process of applying Si to the surface subjected to electrostatic air blowing.
(OR)_4 (R is an alkyl group) A method for manufacturing a cathode ray tube, comprising the steps of spray coating an alcohol solution and then heating and drying.