JPH03112034A - Tubular bulb - Google Patents

Abstract

PURPOSE:To allow hardening at a low temperature in a short time and use resin bases by sticking and fixing the bases and a tubular bulb section via an adhesive layer containing acrylic copolymer and acrylic oligomer. CONSTITUTION:Bases 1 and 1' are stuck and fixed on both ends of a tubular bulb section. Shell sections 5 of bases 1 and 1' are made of resin, and pins 3 are directly planted on them. The cement containing acrylic polymer and acrylic oligomer is used to form an adhesive layer 6. It can be hardened at a low temperature in a short time, thus bases 1 and 1' can be stuck and fixed on the tabular bulb section without generating expansion due to burning or deformation on bases 1 and 1'.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to tubes for straight tube fluorescent lamps, incandescent lamps, compact fluorescent lamps, etc., and particularly to an adhesive layer for adhesively fixing a glass tube and a cap in these tubes.

[Conventional technology]

Tube caps have been widely used in the past, and are compliant with JIS77.
It was standardized in 2009. Among these, the base for straight tube fluorescent lamps, which are most commonly used, uses aluminum for the base part called the shell part, and a Bakelite laminate plate with brass pins embedded in the base part is attached to the base part. are combined. Furthermore, the adhesive used is one in which calcium carbonate is used as a base material, and a phenolic resin and a novolac resin are kneaded together with a solvent such as alcohol. Also, JP-A-50-12838
Publication No. 0 proposes a so-called resin cap made of polyester resin.

[Problem to be solved by the invention]

The above aluminum cap and the glass part of the bulb are fixed by heating, and the temperature at this time is usually 250°C to 350°C.
It is ℃. In this case, the Bakelite laminate often swells due to burning, or the pin implanted part becomes loose due to heat shrinkage. In addition, in completed lamps, electrical conductors made of aluminum can leak electricity due to contact with internal lead-in wires, although this is extremely rare, and even if there is no electrical leakage, there is a potential fear of electric shock for general consumers. Further, in adhering the resin cap and the glass portion of the bulb, conventionally used adhesives have not been put into practical use to date because the heating temperature is high and there is a risk of deformation of the resin. To solve this problem, even if conventional adhesives are used, problems such as blistering and deformation will not occur if the heating temperature is lowered and sufficient time is given, but production efficiency will be significantly reduced. This made it impossible to put it into practical use. In particular, it has been found that for so-called resin caps in which everything except the pin portion is made of resin, the baking temperature needs to be 200° C. or lower in most cases, although it depends on the material of the resin. Furthermore, even when the lamp is used in various environments, the purpose of the present invention is to ensure that the cap does not come off throughout its life. An object of the present invention is to provide a tube provided with an adhesive layer that can eliminate deformation.

[Means to solve the problem]

In order to achieve the above object, in the present invention. The cap and the bulb are adhesively fixed via an adhesive layer containing an acrylic copolymer and an acrylic oligomer. Here, the acrylic copolymer is a polymer obtained from a monomer group containing acrylic acid or methacrylic acid and an ester compound thereof, or a monomer copolymerizable with these monomer groups. In addition, acrylic oligomers include (1) oligoester acrylate, (2)
Refers to a compound having one or more (meth)acrylic groups at the end, such as urethane acrylate and (3) epoxy acrylate. The blending ratio of acrylic copolymer (A) and acrylic oligomer (B) is (A) as solid content weight ratio
/(B) is preferably in the range of 10/90 to 90/10,
More preferably (A)/(B) = 30/70 to 70/3
A range of 0 is good.

[Effect]

Acrylic copolymer (A) and acrylic oligomer (B)
can be mixed with the radical initiator (C), such as an organic peroxide or an azo compound, using an ordinary mixer roll. (C
It is sufficient that the components () are moistened with the components (A) and (B) and mixed uniformly. This liquid-curing adhesive is mixed with an appropriate amount of calcium carbonate, kneaded with alcohol, etc., to a suitable viscosity, and then packed into the mouthpiece. At this time,
Since the curing conditions are a heating temperature of 150° C. to 200° C. and a heating time of about 2 minutes, curing can be performed at a low temperature and in a short time. As a result, conventional problems such as swelling and deformation of the resin material can be completely eliminated. In addition, such adhesives have the property of allowing a long usable life after compounding, and are therefore excellent in improving productivity.

【Example】

Hereinafter, embodiments of the fluorescent lamp will be specifically described with reference to the drawings. FIG. 1 shows the external appearance of a 20 watt straight tube fluorescent lamp, in which bases 1 and 1' are adhesively fixed to both ends of a bulb portion 2, which is the lamp body. Furthermore, the caps 1 and 1' are provided with pins 3 and 3 for supplying power to the bulb section 2, respectively.
3' are implanted respectively. These caps 1, 1' have been used for a long time and are listed in J I 5-C-7709.
has been standardized. FIG. 2 shows a conventionally used cap, in which the shell portion 10 is made of aluminum and the pin 3 is embedded in a Bakelite laminate 4. In FIG. 3, the shell portion 5 is made of resin and is made of PBT (polybutylene terephthalate), into which the pin 3 is directly implanted. FIG. 4 shows a partial cross section of the resin base shown in FIG. 3 fixed to a fluorescent lamp, and 6 indicates an adhesive layer. Conventionally, as mentioned above, this adhesive layer has been made of phenolic resin or novolac resin, so the baking temperature for curing has been carried out at 250°C or higher. In the case of the resin cap shown in FIG. 3, the resin shell 5 was deformed. The resin used to form the shell 5 is PBT (polybutylene terephthalate), which has excellent weather resistance and heat resistance. The cement forming the adhesive layer 6 uses calcium carbonate as a base material, and the adhesives include (A) an acrylic copolymer and (B)
) acrylic oligomer (C) radical initiator (A)/(B) = 50/60, (C)/(
The composition ratio was set to A)+(B)=3/97, and the mixture was mixed using a mixer roll. This was kneaded with calcium carbonate at a ratio of 7:3, the particle size was adjusted with alcohol, and 2.0 g was taken out and filled into the nozzle 5 and baked. The baking conditions were a temperature of 170° C. and a time of 2 minutes. When testing the adhesive strength of the completed fluorescent lamp, it was found that even after 8,000 hours of lighting, the adhesive strength was 3. It was confirmed that the adhesive strength was greater than ON-m. Of course, after completion, the deformation of the resin cap 5 was matched with the overall speed of the fully automatic assembly production line, and no reduction in speed was caused. Next, an example will be described in which the adhesive according to the present invention is used in the conventional cap shown in FIG. 2. Here, the shell 10 is made of aluminum, and 3 is a brass pin embedded in the Bakelite laminate 4. The cement has calcium carbonate as a base material, and the same adhesive as in the above example was used.The baking conditions were such that there was no thermal blistering at all, and the adhesive strength was 3.011 m or more even after lighting for s, o o o hours. was held. These results are summarized in Table 1. In the above embodiment, the base of the straight tube fluorescent lamp was described in detail, but the JISC77 base, which is completely different from that in FIGS. 2 and 3, was described in detail.
The same effect was obtained with the compact fluorescent lamp cap specified in No. 09. Furthermore, the low-temperature curing adhesive of the present invention is similarly effective for light bulb caps in terms of preventing cracks caused by thermal shock in insulating glass. In particular, for the purpose of electrical safety, it will be necessary in the future to make the entire shell part resin, and a low-temperature curing adhesive that is compatible with resin caps will make this possible, which can be said to be a major improvement.

【Effect of the invention】

As described above, according to the present invention, it is possible to harden at a low temperature and in a short time, so that the cap can be adhesively fixed to the bulb portion without causing swelling or deformation of the cap.

[Brief explanation of drawings]

Figure 1 is an external view of the fluorescent lamp according to the present invention, and Figure 2 is A.
FIG. 3 is an external view of the resin cap, and FIG. 4 is a partially cutaway view of the completed lamp fitting. 1.1'...cap, 2...lamp body (bulb part),
3. 3' is a pin, 4... Bakelite laminate, 5...
・Resin shell, 6... Cement (adhesive layer), 10...
metal shell.

Claims (1)

[Claims] 1. A tube section for emitting light, a cap for supplying power to the tube section, and the cap and the tube section for adhesively fixing the cap to the tube section. and an adhesive layer containing an acrylic copolymer and an acrylic oligomer. 2. The tube according to claim 1, wherein the cap is made of resin. 3. The tube according to claim 1, wherein the cap is a metal cap. 4. The tube according to claim 2 or 3, wherein the tube portion is a straight fluorescent tube.