JPS63294662A - Incandescent lamp with reflecting mirror - Google Patents

Abstract

PURPOSE:To prevent falling-off of an incandescent lamp even if a reflection film material is coated on the adhesion face of a reflection mirror by adhering and fixing the base part of the incandescent lamp to one part of the inner face of the reflection film made of glass which is a dichroic reflecting mirror film through an alkali metal silicate adhesive having basic property of PH10. CONSTITUTION:A dichroic reflection film 2 is formed by a vacuum evaporation process or the like by alternatively superposing high deflection ration layers comprising titan oxide dielectric and low deflection ratio layers 15 to 19 times. In this case it is a possibility that one of a reflecting film material 21 adheres to the inner face of a base part 12 while escaping therein. As for an adhesive 4, paste kneaded with alkali silicate by the use of alumina powder as a filler material is filled between the base part 32 of an incandescent lamp and the inner face of the base part 12, while terminal pines 37, 37 are burried in, then the paste is heated and hardened. The adhesive 4 has a basic property of PH10 or more before being baked or after being hardened and can stick directly to the glass face of the base part 12 including coated reflecting film material 21. It is thus possible to prevent falling-off of the incandescent bulb 3 even if the reflection film material is coated on the adhesion face of a reflecting mirror.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a light bulb with a reflector, in which the base end of the light bulb is adhesively fixed to a glass reflector formed with a dichroic reflective film.

(Prior art) In recent years, as a cold light source for spotlights, etc., a dichroic reflective film is provided on the inner surface of a glass reflector with a cylindrical base integrally protruding from the back, and a single-cap type halogen film is installed inside the base. Halogen light bulbs with reflectors that accommodate the base end of the light bulb and are adhesively fixed with a heat-resistant inorganic adhesive are often used.

The above-mentioned dichroic reflective film is composed of 13 to 19 alternate layers of a high refractive index layer made of titanium oxide or the like and a low refractive index layer made of silica or the like, and it reflects visible light well and reflects infrared rays well due to the interference of light 4. It has the property of being transparent.

The above heat-resistant inorganic adhesive is made by kneading metal oxide powder such as alumina with an alkali metal silicate such as water glass, exhibits slight alkalinity with a pH of 8 to 9, and hardens when baked after being interposed between two bonding surfaces. It becomes water-insoluble and exhibits strong adhesive strength. Furthermore, this cured adhesive is highly heat resistant and can withstand the high temperatures of halogen light bulbs without peeling off even after long-term use.

(Problems to be Solved by the Invention) When forming a dichroic reflective film on a glass reflective mirror, a portion of the reflective film material may wrap around the inner surface of the base, forming a film several thousand thick. be. When a light bulb is bonded onto such a reflective film material coating, the adhesive strength is poor, and in severe cases, the light bulb may fall out due to the pressure when the terminal of the light bulb is inserted into the socket. Conventionally, therefore, the inner surface of the base was polished to remove the deposited reflective film material before the light bulb was attached. Moreover, the problem is that the deposited film of the reflective film material is so thin that it is difficult to visually determine whether it is present or not, and therefore, polishing of all the parts is unavoidable, which requires a great deal of effort.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a light bulb with a reflector to which a light bulb can be bonded without removing the reflective film material on the part of the glass reflector that is to be bonded. By adhering and fixing the base end of the light bulb to a part of the inner surface of the formed glass reflective film through an alkali metal silicate adhesive having a basicity of pH 10 or higher, the reflective film material It is designed so that it will not peel off even if it is adhered to the adhered film.

(Function) Alkaline silicate adhesives are represented by the molecular formula M, O・n5io2, and the type of M (Li, Na, K, etc.) and n
There are many types depending on the size of the glass, and in general, sodium silicate (water glass) is often used. When heated, dehydration condensation reaction occurs between silanols, forming siloxane bonds between molecules, forming water resistance and exhibiting adhesive strength. Then, it reacts with the alkali silicate, solidifies, and adheres to the glass surface. Therefore, the reflective film material can be adhered to the glass surface without removing it.

(Example) The details of the invention will be explained by means of illustrated embodiments.

■ is a glass reflector, ■ is this reflector (dichroic reflective film formed on the inner surface of υ, ■ is a light bulb installed inside the reflector ω, (a) is this light bulb ■ as a part of the inner surface of the reflector ■ It is an adhesive that sticks.

The above reflector ■ is made of hard glass integrally molded, and its inner surface forms a paraboloid of revolution with an outer diameter of 50! Reflection part of I11 (11)
A cylindrical base portion (12) with an open bottom is integrally provided on the back surface of the device.

The above-mentioned dichroic reflective film ■ has a high refractive index layer made of a titanium oxide dielectric and a low refractive index layer made of a silica dielectric.
It consists of 5 to 19 alternate layers, and is formed by an appropriate method such as vacuum deposition or thermal decomposition of an organic metal compound coating, and has the property of reflecting visible light and transmitting infrared rays due to light interference. have

As a result, a portion of the reflective film material (21) often wraps around into the base portion (12) and undesirably adheres to the inner surface.

The above light bulb ■ is made by crushing and sealing the base end (32) of a cylindrical quartz glass bulb (31) and attaching a pair of molybdenum introduced foils (33).
), (33), and these introduced foils (33), (
A pair of inner core wires (34), (34) connected to the bulb (33) were extended into the bulb (31), a filament (35) was mounted thereon, and the filament (35) was connected to the lead-in foil (33), (33). A pair of outer conductor wires (36) and (35) are brought out from the end surface of the base end (32) and connected to the terminal pins (37) and (37). Then, necessary halogen is introduced into the valve (31) together with an inert gas such as argon. Then, the base end (32) is positioned in the base part (12) so that the filament (35) is located at the focal point of the reflective part (11), and the terminal pins (37), (37) are placed in the base part. (1
2) Extend outward.

The above adhesive is made by filling a paste made by mixing alkali silicate with alumina powder as a filler between the bulb base end (32) and the inner surface of the cap (12), and also filling the terminal pin (
37), (37) was buried and heated to harden. One of the features of the present invention is that this adhesive exhibits alkalinity with a pH of 10 or more before baking. Further, even after curing, although it is water-insoluble, it has a basicity higher than PHLO. Then, when the adhesive hardens, the entire paste solidifies and is directly adhered to the glass surface of the cap part (12), including the reflective film material (zl) adhered to the inner surface of the cap part (12). ing.

As mentioned above, the reflector-equipped light bulb of this embodiment is basic with a pH of 10 or more, so even if the reflective film substance (21) is attached to the inner surface of the base (12), it can be directly applied to the glass surface without being hindered by this. It has strong adhesion, and the adhesive (a) will not peel off from the glass surface even after long-term use, and the adhesive (b) will not deteriorate.

Next, the relationship between the basicity of the adhesive and adhesive strength was investigated. For the reflective mirror (■), use one that has a reflective film substance (21) attached to the entire inner surface of the base (12), and use an adhesive (A).
For this purpose, a plurality of types having various pH values measured at the time of pasting were selected and used. Then, the light bulb with a reflector shown in the drawings was constructed by a conventional method. Next, the obtained light bulb with a reflector was placed in a compression tester, and pressure was applied so that the light bulb would come out, and the pressure when the light bulb came out was measured.

The results are shown in the table below. The pressure values in the table are the average of 5 test products. From this table, when the pH at the time of pasting is 10.0 or higher, the adhesive strength is extremely high even in the presence of reflective film material, and there is no risk of the bulb falling off. I can understand that. When the basicity of the adhesive after curing was measured for these test products, it showed a value similar to the pH before curing. Therefore, in the present invention, the basicity of the adhesive after curing is limited to PH10 or higher.

In the above-mentioned examples, the adhesive used was alumina powder mixed with an alkali silicate as a filler, but the present invention is not limited to this. But it's okay, the point is PH10
Any alkali silicate adhesive having a basicity of 1 or more is sufficient. Also, the glass constituting one reflecting mirror may be soft glass, and the light bulb may be an ordinary light bulb.Furthermore, the base is not essential; It is sufficient if the base end of a light bulb is glued to a part of the inner surface of a glass reflector provided with a dichroic reflective film.

〔Effect of the invention〕

As described above, in the light bulb with a reflector of the present invention, a dichroic reflective film is formed on the inner surface of the glass reflector, and a part of the inner surface of the light bulb is coated with an alkali silicate adhesive having a basicity of pH 10 or higher. Since the base end is fixed with adhesive, strong adhesion is possible even if reflective film material is adhered to the adhesive surface of the reflector, and there is no risk of the bulb falling off even after long-term use.
It is no longer necessary to remove the reflective film material on the surface to be bonded during the manufacturing process.

[Brief explanation of the drawing]

The drawing is a sectional view of one embodiment of the light bulb with a reflector according to the present invention. ■...Reflector (11)...Reflector (12
)...Made part ■...Dichroic reflective film (
21)...Reflective film material ■...Light bulb (31)...
・Valve (32)... Base end (35)...
Filament (37)... Terminal pin (a)... Adhesive agent Patent attorney Inoue - Oen I

Claims (1)

[Claims] The base end of the light bulb is adhesively fixed to a part of the inner surface of a glass reflector with a dichroic reflective film formed on the inner surface using an alkali metal silicate adhesive having a basicity of pH 10 or higher. A light bulb with a distinctive reflector.