JPH0677436B2 - Fluorescent lamp manufacturing method - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for manufacturing a fluorescent lamp, and more particularly to a method for increasing the adhesive strength of a phosphor layer to the inner surface of a glass tube in a fluorescent lamp.

[Background of the Invention]

Conventionally, when a fluorescent substance is applied to the inner surface of a glass tube for a fluorescent lamp, for example, the fluorescent substance is suspended in a solution of nitrocellulose as a binder in an organic solvent butyl acetate, and this is suspended on the inner surface of the glass tube. The phosphor layer is formed by applying, drying and baking steps. However, in recent years, water-soluble binders have been used because of problems such as resource saving, energy saving, and working environment.

In general, this water-soluble binder has a weaker strength for adhering the phosphor layer to the inner surface of the glass tube as compared with a conventional organic solvent binder, and is extremely easy to peel off.

In particular, when the water-soluble binder is polyethylene oxide, the peeling phenomenon of the phosphor layer appears remarkably. Therefore, for the purpose of increasing the adhesion strength of the phosphor layer to the glass tube, for example, as disclosed in JP-A-58-126658, at least one of strontium nitrate and barium nitrate, boric acid, and boric anhydride. It has been proposed to add at least one of and calcium pyrophosphate to the phosphor coating.

However, when the phosphor layer is formed on the inner surface of the glass tube for a rapid start fluorescent lamp having a transparent conductive coating such as tin oxide on the inner surface of the glass tube, the above-mentioned peeling phenomenon becomes more remarkable.

In this case, the adhesive strength of the phosphor layer is increased by increasing the addition amount of the above-mentioned adhesive strength increasing agent, but the Nesa resistance after the lamp is completed is increased, and especially the enclosed rare gas is a mixed gas containing krypton. There is a problem that the starting characteristics of a power-saving rapid start type fluorescent lamp using a gas, for example, a mixed gas of krypton and neon, deteriorates.

[Object of the Invention]

The object of the present invention is to increase the adhesive strength of the phosphor layer to a glass tube by using a fluorescent paint using an aqueous solution of a water-soluble binder, and to form a transparent conductive film such as tin oxide on the inner surface of the glass tube. Another object of the present invention is to provide a method of manufacturing a fluorescent lamp which can improve the starting characteristics of a power saving type rapid start fluorescent lamp or the like using a mixed gas containing a krypton as an enclosed gas.

[Outline of Invention]

In order to achieve the above-mentioned object, a halophosphate phosphor activated with Sb or Sb and Mn, at least one selected from the group consisting of strontium nitrate and barium nitrate, boric acid, and A step of applying a phosphor suspension prepared by adding at least one selected from the group consisting of boric anhydride and an adhesive strength increasing agent consisting of a chloride of an alkaline earth metal to the inner surface of a glass tube; It is characterized in that the fluorescent lamp is manufactured through the subsequent drying step and firing step.

By the characteristic manufacturing method of the present invention, the adhesion strength of the phosphor layer to the glass tube can be extremely increased, and as a result, a fluorescent lamp of extremely excellent quality can be manufactured. I was able to do it.

Example of Invention

 Hereinafter, the present invention will be described in detail with reference to examples.

Example 0.8 of polyethylene oxide as water-soluble binder
Weight percent water solubility is used. To 150 cc of this aqueous solution of polyethylene oxide, 100 g of halophosphate phosphor (white) activated with Sb or Sb and Mn was added, and barium nitrate [Ba (NO ₃ ) ₂ ] and anhydrous borohydride were used as adhesion strength increasing agents. Acid (B ₂
O ₃ ) and a predetermined amount of strontium chloride (SrCl ₂ ) are added. This solution is then ball milled for 30 minutes to form a phosphor suspension.

This suspension is applied to the inner surface of a glass tube for a rapid start fluorescent lamp (for 40 W) having a transparent conductive coating of tin oxide on the inner surface of the glass tube. Then, this glass tube is dried and baked under normal conditions. After that, after a normal manufacturing process, the enclosed gas is krypton: neon = 65: 3.
We have manufactured a power saving rapid start type fluorescent lamp with 5% capacity.

Table 1 shows the adhesive strength of the phosphor layer of the fluorescent lamp to which the adhesive strength increasing agent of the typical combination among the various adhesive strength increasing agents mentioned above is added and the starting of the lamp at 25 ° C. And the voltage.

Here, the adhesive strength in Table 1 is defined as follows. That is, as a measure of the strength of adhesion of the phosphor layer to the inner surface of the glass tube, the degree of peeling of the phosphor layer caused when a shock was applied to the outer surface of the fluorescent lamp with a piano wire having a load equivalent to 150 g. The size is represented by the average diameter (mmφ). Further, the amount of the adhesive strength increasing agent added is shown in% by weight with respect to the phosphor.

In Table 1, Nos. 1 to 3 are conventional fluorescent lamps shown for comparison with Nos. 4 to 10 according to the present embodiment.

No. 1 is the case where no adhesive strength increasing agent is added, and the adhesive strength of this fluorescent lamp is extremely weak and cannot be put to practical use. No. 2 is a case in which 0.3% by weight of Ba (NO ₃ ) _{2 and} 0.3% by weight of B ₂ O _{3 are} added, and there is no problem in the starting voltage, but the adhesion strength is weak. No. 3 was added with 0.5% by weight of Ba (NO ₃ ) _{2 and} 0.5% by weight of B ₂ O _{3 in} order to increase the adhesive strength. In this case, there is no problem with the adhesive strength, but the starting voltage becomes extremely high. It turns out that it cannot be put to practical use.

No.4~10 is _{Ba (NO 3) 2, B} 2 O 3 , and shows the various combinations of the added amount of SrCl _2, both without problems sufficiently practical adhesive strength and the starting voltage of the fluorescent body layer It was confirmed that a fluorescent lamp that can be used for

Although the above examples show the combination of Ba (NO ₃ ) ₂ , B ₂ O ₃ and SrCl ₂ , Sr (NO ₃ ) ₂ or Ba instead of Ba (NO ₃ ) ₂
Almost the same effect can be obtained by using (NO ₃ ) ₂ and Sr (NO ₃ ) ₂ . Also has a substantially similar effect be used instead of B ₂ O ₃ and H ₃ BO ₃ or B ₂ O ₃ and H ₃ BO _3.

In addition, when an experiment was conducted in which the addition rate of the adhesive strength increasing agent was variously changed, the following was found.

That is, the addition amount of Ba (NO ₃ ) ₂ and Sr (NO ₃ ) ₂ is 0.05 to 0.
A range of 7 weight percent is desirable. The reason is that if the addition rate is less than 0.05% by weight, the adhesive strength will be lowered, and if it exceeds 0.7% by weight, the adhesive strength is improved but the starting voltage tends to increase, which is not desirable. Also,
The addition ratio of B ₂ O ₃ and H ₃ BO ₃ is preferably in the range of 0.05 to 0.5% by weight. The reason is that if the addition rate is less than 0.05% by weight, the adhesive strength will be reduced, which is not desirable. In the case of a shaped fluorescent lamp, the starting voltage rises remarkably, which is not preferable.
The addition rate of chloride of alkaline earth metal, for example, SrCl ₂ or BaCl ₂ is preferably in the range of 0.05 to 0.5% by weight.
The reason for this is that if the addition rate is less than 0.05% by weight, the adhesive strength will decrease, and if it exceeds 0.5% by weight, the luminous flux of the lamp will decrease, which is not desirable.

Although the power-saving rapid-start fluorescent lamp has been described in the above embodiment, similar results were obtained with other straight-tube fluorescent lamps.

〔The invention's effect〕

As described above, according to the present invention, it becomes possible to provide a fluorescent lamp in which the adhesion of the phosphor layer to the inner surface of the glass tube is extremely large, and the contribution to the quality improvement is extremely large.

Claims (4)

[Claims] 1. A water-soluble binder aqueous solution containing Sb or Sb
A halophosphate phosphor activated with Mn, at least one selected from the group consisting of strontium nitrate and barium nitrate, at least one selected from the group consisting of boric acid and boric anhydride, and an alkaline earth metal A step of applying a phosphor suspension prepared by adding an adhesion strength increasing agent consisting of chloride to the inner surface of the glass tube, and a step of blowing hot air into the glass tube to dry it after the applying step. And a step of heating and firing the glass tube after the drying step, the method for manufacturing a fluorescent lamp. 2. The addition ratio of the adhesive strength increasing agent to the phosphor is strontium nitrate or barium nitrate.
0.05 to 0.7% by weight, boric acid or boric anhydride in the range of 0.05 to 0.5% by weight, and alkaline earth metal chloride in the range of 0.05 to 0.5% by weight. A method of manufacturing a fluorescent lamp according to item 1. 3. The method for producing a fluorescent lamp according to claim 1, wherein the chloride of the alkaline earth metal is at least one of strontium chloride and barium chloride. . 4. The water-soluble binder is polyethylene oxide, according to any one of claims 1 to 3.
Method for manufacturing fluorescent lamps in one section.