JPS609038A - Picture tube - Google Patents

Abstract

PURPOSE:To provide a picture tube which produces practically no high voltage charging on the external surface of the face panel portion and no mirror reflection from the same, by applying a colloidal film of siloxane to the external surface of the face panel portion. CONSTITUTION:The picture tube 1 is provided with a reinforcement (implosion protecting) metallic band 5 disposed at the region where the panel portion 3 of the glass bulb 2 and the funnel portion 4 are sealed together and its face panel portion 3 is provided with a 0.05mum-1mum thick colloidal film 6 applied to the external surface thereof. The fringe portion of the film is kept in contact with the metallic band 5 which is at the ground potential. By such arrangement, the risk of high voltage charging can be remarkably reduced and the mirror reflection phenomenon on the external surface of the face panel portion which will reflect a bright window, fluorescent lamp, and the like from the surface can be prevented virtually completely.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides an image receiving device in which a colloidal film of siloxane is attached to the outer surface of the face panel of a glass bulb to prevent high-voltage charging and specular reflection of external light on the outer surface. Regarding pipes.

Conventional Structures and Problems Generally, picture tubes incorporated in television receivers and the like operate at an accelerating voltage of 10 KV to 30 KV, so the outer surface of the glass pulp face panel is likely to be charged to a high potential. When such high-voltage charging occurs, there is not only a risk of electric shock, but also charged dust in the air adheres to the outer surface, making it difficult to view reproduced images.

Further, when external light from bright windows, fluorescent lights, etc. causes specular reflection on the outer surface of the face panel, the reproduced image becomes even more difficult to see.

In particular, picture tubes in computer terminal equipment, word processors, etc. face the operator at a close distance (clear viewing distance) of approximately 30C[11], so there is a possibility that the human body may touch the outer surface of the face panel while using a light pen, etc. Therefore, it is very important to prevent the high-voltage charging and specular reflection from psychological and physiological viewpoints.

Conventionally, cationic or anionic surfactants have been applied to the outer surface of the face panel of picture tube glass bulbs to make them conductive, but surfactants are water-soluble. Therefore, it could be easily removed by touching it with a fingertip or wiping it with a wet cloth, making it impossible to provide a durable antistatic means.

On the other hand, in order to prevent specular reflection of external light as mentioned above, a multilayer metal vapor deposition film is formed on the outer surface of the face panel of a glass bulb. This requires considerable expense, leading to high costs. However, in picture tubes in which the outer surface of the face panel is roughened by etching or the like to scatter external light incident on the outer surface, the reproduced image produced on the phosphor screen surface is affected by sparkling light due to the unevenness of the outer surface. Since this results in so-called rough light emission, anti-reflection measures using such surface roughening treatment are not particularly suitable for high-definition picture tubes.

Purpose of the Invention The present invention is based on the fact that the above-mentioned sparkling phenomenon depends on the height and pitch of the unevenness on the outer surface of the glass bulb face panel, and that fine particles can be removed without optical contact with a thin film of a material having a different refractive index at the glass interface. This was done based on the fact that when coated and formed into a shape, the light scattering effect on the surface becomes dusty. SUMMARY OF THE INVENTION In the picture tube of the present invention, the outer surface of the face panel of the glass bulb is coated with siloxane, i.e. , (S i→-8
i) A thin colloidal (white cloudy) film made of n-chains with a thickness of approximately 0.05 μm to 1 μm is formed, and a portion of the film is brought into contact with a reinforcing metal band attached to the glass bulb. will be described in detail below with reference to embodiments shown in the drawings.

DESCRIPTION OF THE EMBODIMENTS In FIG. 1, a 14-inch color picture tube 1 has a glass bulb 2 with a face panel portion 3 and a funnel portion 4.
A reinforcing metal band 6 surrounding the area is attached to the vicinity of the sealing area, and a colloidal film 6 made of siloxane and having a thickness of about 5 μm to 1 μm is attached to the outer surface of the face panel portion 2. Become. However, the membrane 6 not only completely covers the front surface of the face panel section 3 but also extends to the side peripheral surface, and the outer peripheral edge of the membrane is in contact with the metal band 5 which is at ground potential. Colcoat P liquid (trade name) manufactured by Colcoat Chemical Co., Ltd. can be used. In this case, first, 90 parts of Colcoat P liquid and 10 parts of methoxyalcohol are mixed to prepare mixed A liquid. Next, heat the color picture tube 1J7) glass bulb 2,
The mixture A liquid is air-sprayed onto the outer surface of the face panel portion 3 whose temperature has reached 0°C to 0°C. Nozzle hole diameter 0.5mm
The amount of mixed A liquid sprayed with 2 atm high pressure air from the spray gun is 910 rrl to 30 rrl per picture tube.
m1, and the film thickness on the outer surface of the face panel portion 3 is approximately 0.05 μm to 1 μm.

The surface state of the film 6 thus obtained is uneven, as seen from the micrograph (magnification 200) in FIG. 2, and scatters incident light. The degree of light scattering was approximately 56 in glossiness (cross value), an index representing the degree of light scattering. In addition, the amount of Kolko P solution in the mixed human fluid is 7
It can be selected from a range of 0 to 95 parts. Further, the diluent that promotes clouding is not limited to methyl alcohol, but may also be ethyl alcohol, butyl alcohol, or a water-containing substance thereof.

When the color picture tube equipped with the film 6 is operated under normal operating conditions, the outer surface potential of the face panel becomes OV immediately after energization, as shown by curve a in FIG. Compared to the characteristics of In addition, it was possible to almost completely prevent specular reflections caused by bright windows, fluorescent lights, etc. on the outer surface of the face panel.

The second embodiment of the present invention is as follows.

That is, first, 85 parts of Colcot N-103X liquid (trade name) manufactured by Nippon Colcoat Chemical Co., Ltd. and 15 parts of ethyl alcohol are mixed to prepare a mixed solution B. Next, 12
A thin layer of silane coupling agent is applied to the outer surface of the glass bulb face panel of an inch-type monochrome picture tube, from the entire front surface to the reinforcing metal band on the side circumference, and this is applied at a temperature of approximately 50°C. dry. As a silane coupling agent, for example, K manufactured by Shin-Etsu Chemical Co., Ltd.
BC1o003- (trade name) can be used to kill. After the applied silane coupling agent has dried, the mixed B liquid is sprayed onto the same area using an air spray.The amount of spraying is 2 to 30 m per picture tube.
β, and other spray conditions are the same as in the previous example. After spraying, let it air dry at room temperature.

The outer surface of the face panel of the picture tube subjected to such film forming treatment becomes rough as in the above-mentioned embodiment.
The photoselectivity can be 45-65.

Since the incident light is strongly scattered, specular reflection is drastically reduced. Similar to the above-mentioned example, a remarkable high-voltage antistatic effect was obtained.

Effects of the Invention Since the present invention is constructed as described above, by simply performing a relatively simple film forming process, it is possible to obtain a picture tube in which high-voltage charging and almost no specular reflection occur on the outer surface of the face panel portion. .

[Brief explanation of drawings]

Fig. 1 is a partially cutaway perspective view of a picture tube in which the present invention is implemented, Fig. 2 is a micrograph showing the surface condition of the membrane attached to the outer surface of the face panel of the picture tube, and Fig. 3 is a photoreceptor of the picture tube. FIG. 3 is a characteristic diagram comparing the change characteristics of the outer surface potential of the face panel portion with respect to the time after the start of energization of the tube with the same change characteristics of a conventional picture tube. 3...Face panel part, 5...Metal band, 6...Colloidal film of siloxane. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Tr After the opening meeting M (Intermediate) Procedural amendment (Representation of Utility Act 1 case 1988 Patent Application No. 116336 2 Name of the invention Picture tube 3 Person making the amendment Old '1) Relationship with Ina ゛ Application Address: 1006 Kadoma, Kadoma City, Osaka Name (584) Matsushita Electronics Co., Ltd. Representative Kiyoshi Miyama - 4 Agent Address: 571 Osaka JF1] Oaza, Kadoma City Uchikarasu, Matsushita Electric Industrial Co., Ltd., 1006 Kadoma. Contents of correction (1) 1.Surface condition on page 8, line 5 of the specification will be corrected to ``particle structure.''

Claims (1)

[Claims] A colloidal film made of siloxane with a thickness of approximately 0.95 μm to 1 μm is attached to the outer surface of the face panel of the glass bulb, and a portion of the film is brought into contact with a reinforcing metal band attached to the glass bulb. Characteristic picture tube.