JPS62100926A - Formation of fluorescent film - Google Patents

Abstract

PURPOSE:To make the thickness of a fluorescent film even, by applying aluminate phosphor particles attached with micropowder of silicon oxide thereover. CONSTITUTION:Over a base plate 1 is formed an adhesive layer 8, and a desired position 8a of the layer 8 is made adhesive. Over the surface of aluminate phosphor particles 6, micropowder 7 of silicon oxide is attached, and the resultant mixtures are fed on the base plate 1, excessive mixtures being removed. In such a way, the particles 6 which have a strong condensation each other and a large adhesiveness to the base plate 1 can be converted to lose the adhesiveness to the undesired portions by adding only small amount of silicon oxide 7, and an even thickness of the fluorescent film 9 can be formed.

Description

[Detailed description of the invention] ；゛-の'1 The present invention relates to a method for forming a fluorescent film.

W crotch Δ skin "One of the methods of forming a fluorescent film of a cathode ray tube is
There is a method (dry) disclosed in Japanese Patent No.-38732.

As shown in FIG. 7, this method first forms a layer 2 of a photosensitive adhesive that develops tackiness upon exposure to light on a substrate 1, and then exposes a desired portion of this substrate 1 to light to partially make it hygroscopic. The adhesive layer 3 absorbs moisture and is left to stand for a predetermined period of time to form a moisture-absorbing adhesive layer 3 on a desired portion of the substrate 1 as shown in FIG. Then, as shown in FIG. 9, phosphor powder 4 is supplied onto this substrate 1 and spread, thereby adhering the phosphor 4 onto the adhesive layer 3. At this time, multiple layers of phosphor particles adhere to the adhesive layer 3 due to moisture creeping up. Then, when the excess phosphor powder is removed, a phosphor film 5 is formed at a desired portion as shown in FIG.

In this manufacturing method, a striped exposure pattern mask is used, and phosphor powders emitting different colors are attached to each striped exposed portion, thereby easily producing a phosphor film for a color television.

Although the above-mentioned adhesive is a photosensitive adhesive, for example, a photosensitive adhesive has been described, in the case of a monochrome fluorescent film or the like, an adhesive such as zinc chloride that becomes hygroscopic without exposure to light may be used.

-, Roy',,0 By the way, aluminate phosphor (Y3Al
When sO+2'C8, Y3AIsOi2'Tb, etc.) were used, the adhesion between the phosphor powders or between the phosphor and the substrate was so strong that they formed clumps, making it impossible to form a phosphor film with a uniform thickness.

In response to this, the inventors have previously proposed that by adding a predetermined amount of fine alumina powder to the phosphor particles, the cohesive force between the phosphor particles can be reduced, making it easier to form a phosphor film. (Japanese Patent Application No. 59-204610) However, even if fine alumina powder was added to the aluminate phosphor, the cohesive force could not be reduced.

The present invention was proposed in view of the above problems, and when forming a phosphor film by a dry method, if the phosphor is an aluminate phosphor, fine powder of silicon oxide is mixed in advance. It has been discovered that a homogeneous fluorescent film can be formed by using a fluorescent substance.

Embodiments of the present invention will be explained below with reference to FIGS. 1 to 6. FIG. 1 shows a phosphor film produced according to the invention, in which a fine powder 7 of silicon oxide (Si20) is attached around an aluminate phosphor 6 deposited on a substrate 1. The manufacturing method is shown in FIGS. 2 to 6.

First, as shown in FIG. 2, a substrate 1 on which an adhesive layer 8 is formed is prepared, and a desired portion 8a of the adhesive layer 8 is formed as shown in FIG.
to develop stickiness. Then, as shown in FIG.
A sufficient amount is supplied onto the substrate 1 as shown in the figure.

Then, the remaining phosphor is removed from the substrate 1, and a phosphor film 9 can be formed on a desired portion 8a of the adhesive layer.

Here, the silicon oxide mixed in advance with the aluminate phosphor has an average particle size of 5 to 100μ and a mixing ratio of 0.1 to 10ωt.
Good results were obtained with %.

As described above, according to the present invention, a small amount of silicon oxide fine particles is added to an aluminate phosphor that conventionally has a large cohesive force between phosphor particles and also has a large adhesion force to a substrate. This eliminates adhesion to undesired areas, makes it possible to form a phosphor film with a uniform thickness, and improves display quality.

[Brief explanation of drawings]

Figure 1 is a side sectional view showing a fluorescent film to which the present invention is applied;
6 to 6 are side sectional views showing an embodiment of the present invention, and FIGS. 7 to 10 are side sectional views showing a method of forming a fluorescent film by a dry method. 1...Substrate, 6...Aluminate phosphor. 7... Fine powder of silicon oxide, 9... Fluorescent film. Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 rA Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] A method for forming a phosphor film, characterized in that fine powder of silicon oxide is mixed in advance with the aluminate phosphor when forming the phosphor film by adhering the phosphor to a substrate via an adhesive layer.