JPS6236479A - Method of bonding photosensitive resin - Google Patents

Abstract

PURPOSE:To cure a photosensitive resin adhesive using a radiation device which fully exhibits the capability, by blowing an inert gas from under a belt in a continuous ultraviolet radiation device in order to remove oxygen present in the recessed portions, followed by radiation of ultraviolet rays from above the belt. CONSTITUTION:A nitrogen gas which has been injected at a high speed from pores provided at the top of an injection nozzle 71 is passed through a belt 5, fed into the recessed portions of a side 3 and passed through an inlet 41. This removes the residual oxygen, which has been brought into the inside of the device, from the inside of the recessed portions, to thereby convert the atmosphere of the inside of the recessed portions into an inert atmosphere. The residual oxygen which has been removed from the inside of the recessed portions is diluted with the nitrogen gas which is continuously fed from the injection nozzle 71. Further, the inside of the continuous ultraviolet radiation device equipped with an injection nozzle for an inert gas is maintain at a positive pressure relative to the atmospheric pressure by means of the nitrogen gas. Therefore, the residual oxygen gas is regularly discharged together with the nitrogen gas into the outside through the inlet 41 and outlet 42. For this reason, the inert atmosphere of the whole inside of the device is also maintained with the high-purity nitrogen gas. Therefore, a photosensitive resin adhesive 34 is cured upon exposure to ultraviolet rays 2, since oxygen which hinders the photosensitive reaction is present only in a trace amt.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention involves applying a photosensitive resin adhesive, combining a plurality of parts to form a concave shape, and curing the photosensitive resin adhesive using a continuous ultraviolet irradiation device. This invention relates to a photosensitive resin adhesion method.

[Conventional technology]

FIG. 2 is a longitudinal sectional view showing an example of a conventional continuous ultraviolet irradiation device. The interior surrounded by the cover 4 is always filled with N2 gas supplied from the gas supply port 6. belt 5
is formed into a ring-shaped cross section, and rotates to repeatedly perform constant-velocity operation. Then, set the watch side 3 on the top surface outside the cover 4, enter the inside of the device from the inlet 41, pass through the N2 gas atmosphere, and then exit 42.
After going out into the atmosphere and operating in an oxygen atmosphere, after removing the side 6, the side 6 is placed on the upper surface again and the device enters the inside of the device through the inlet 41. The concave watch sides 3 are set one after another on the belt 5 with the opening facing down outside the inlet 41, and are passed through the inlet 41 according to the operation of the belt 5, creating the N2 gas atmosphere. Inside the continuous ultraviolet irradiation device, ultraviolet rays 2 are evenly irradiated from an ultraviolet lamp 1 toward the upper surface of the belt 5.As the belt 5 operates, the side 6 of the wristwatch is exposed to the entrance. 41
The photosensitive resin adhesive 34 shown in FIG. 3, which will be described later, is cured by being exposed to ultraviolet rays 2 during this time.

FIG. 3 is an enlarged longitudinal sectional view of the side of the wristwatch in FIG. 2. The side 6 consists of a side body 32 and a glass 61, and between the parts of both the side body 62 and the glass 61 there is a photosensitive resin adhesive 34 applied in a layer. The photosensitive resin adhesive 34 is cured by the ultraviolet light 2 irradiated onto the belt 5.

A concave interior 33 surrounded by side 3 is semi-enclosed by belt 5 and side 3.

[Problem that the invention seeks to solve]

As described above, the photosensitive resin adhesive 64 undergoes a curing reaction by being irradiated with ultraviolet rays 2 from above for a certain period of time, thereby bonding the glass 61 and the side body 62. At this time, if the atmosphere at the time of UV 2 irradiation is oxygen, the start of the curing reaction will be inhibited and the time required for the reaction will be long. An attempt was made to create an N2 gas atmosphere inside the device using the cover 4 of the device to accelerate the curing reaction of the photosensitive resin adhesive 34.However, as shown in FIG. Concave interior configured6
Since the opening of the inlet 4 faces downward and the concave interior 36 is in a semi-sealed state surrounded by the belt 5 and the side 6, the inlet 4
When the side 6 is set outside the device 1, the oxygen inside the concave interior 66 remains without being replaced by the N2 gas inside the device and is irradiated with ultraviolet rays 2, so that the adhesive layer remains in contact with oxygen. End portion 341 could not be sufficiently cured.

In other words, even with the conventional technology shown in Fig. 2, the original purpose of accelerating the curing reaction rate through ultraviolet irradiation in an N2 gas atmosphere can be achieved. When exposed to general light, the uncured portion of the photosensitive adhesive 34 gradually hardens, and the corrosive gas generated during the curing process corrodes internal parts of the watch, such as the dial surface, making it unusable as a product. There were also problems such as loss of value. The present invention has been made to solve the above problems, and its purpose is to provide a highly reliable and productively efficient photosensitive resin bonding method that fully demonstrates the functions of an ultraviolet irradiation device in an inert atmosphere. It is in.

[Means for solving problems]

In order to achieve the above object, the present invention applies a photosensitive resin adhesive and combines a plurality of parts to form a concave shape, and makes the concave opening formed by combining the parts downward to provide ventilation. Set on a belt, inert gas is blown from below the belt in a continuous ultraviolet irradiation device to eliminate oxygen inside the concave mold, and ultraviolet rays are irradiated from above to harden the photosensitive resin adhesive. It is characterized by allowing

〔Example〕

FIG. 1 shows an embodiment of the present invention, and is a longitudinal sectional view of a continuous ultraviolet irradiation device equipped with a N2 gas injection nozzle. cover 4
．． The inside of the device surrounded by the inlet 41 and the outlet 420 are isolated from the outside air, and N2 gas is constantly supplied to the inside of the device from the injection nozzle 71 through the inert gas supply pipe 7. There is. Although the inlet 41 and the outlet 42 are always open, the amount of N2 gas supplied from the injection nozzle 71 is adjusted so that the N2 gas is always at a positive pressure with respect to the atmospheric pressure inside the device. There is no backflow inside. The belt 5 is made of fluorinated ethylene with a mesh interval of approximately 3 mm, and has extremely good air permeability. The injection nozzle 71 is arranged close to the bottom of the belt 5, and as described above, the N2 gas supplied from the injection nozzle 71 always blows through from the lower surface of the belt 5 to the upper surface. Furthermore, the N2 gas that has blown through the belt 5 is placed on the belt 5 with the opening inside the concave facing down, and is directly applied to the inside of the concave on the side 3 of the moving wristwatch. The ultraviolet light 2 irradiated from the ultraviolet lamp 1 toward the belt 5 is aligned on the upper surface of the belt 5, and as the belt 5 is operated, it is irradiated from the inlet 41 toward the outlet 42 toward the operating side 6. ing.

FIG. 4 is an enlarged vertical sectional view of the belt and sides in FIG. 1. Side 3, which is composed of side main body 32 coated with photosensitive resin adhesive 34 and glass 61 and forms a recess, is placed on belt 5 with the opening of the recess facing downward, and side 3
The belt 5 arranged with
It is working towards 2. The N2 gas ejected at high speed from the pore at the tip of the injection nozzle 71 passes through the belt 5, enters the inside of the concave mold on the side, passes through the inlet 41, and expels residual oxygen brought into the inside of the device from the inside of the concave mold. An inert atmosphere is created inside the concave mold. - The concentration of the residual oxygen expelled from the inside of the Mansei mold is reduced by the N2 gas supplied one after another from the injection nozzle 71. Moreover, the inside of the continuous ultraviolet irradiation device with an inert gas injection nozzle is exposed to the N2 gas. Since the pressure is kept positive with respect to atmospheric pressure, it is constantly discharged to the outside from the inlet 41 and outlet 42 along with the N2 gas.Therefore, the entire interior of the device is also maintained in an inert atmosphere with high-purity N2 gas. As mentioned above, since there is a small amount of oxygen that inhibits the photosensitive reaction, the photosensitive resin adhesive 64 that is irradiated with ultraviolet rays 2 is immediately photocured. The adhesive layer end portion 341 inside was also cured stably and uniformly in a short time.

In this example, the conventional method required 360 seconds to complete curing, but
It was fully cured in 6 seconds. Therefore, it has become possible to increase the operating speed of the belt 5 by ten times compared to the conventional method.

Although this embodiment was used to join the watch side body and the glass, the present invention can be applied if one opening is closed and joined with another part to form a concave shape. is possible.

〔Effect of the invention〕

As mentioned above, in the past, the residual oxygen inside the concave mold significantly impaired the quality reliability of products and hindered productivity, but the present invention eliminates the negative effects of the residual oxygen, shortens the reaction time, and reduces production costs. By making the adhesive cured layer chemically stable, it has become possible to produce highly reliable products despite having complex shapes.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, and is a longitudinal sectional view of a continuous ultraviolet irradiation device equipped with an inert gas injection nozzle. FIG. 2 is a longitudinal sectional view showing an example of a conventional continuous ultraviolet irradiation device. Figure 3 is a vertical cross-sectional view of the wristwatch in Figure 2, and Figure 4 is a vertical cross-sectional view of the wristwatch in Figure 2.
It is a longitudinal cross-sectional view of the belt and the side in a figure. 1...Ultraviolet lamp, 2...Ultraviolet light,
3... side, 31... glass, 32...
... Side body, 34 ... Photosensitive resin adhesive, 341 ... Adhesive layer end, 4 ... Cover, 5 ... Belt, 7... Inert gas supply pipe, 71... Injection nozzle. Patent applicant Citizen Watch Co., Ltd. Tama Seimitsu Co., Ltd. Figure 1 Figure 4 3177 Fmata

Claims (1)

[Claims] A photosensitive resin adhesive is applied and multiple parts are assembled to form a concave shape, and the concave opening formed by combining the parts is set on a ventilated belt with the opening of the concave shape facing downward, and then continuously irradiated with ultraviolet rays. Photosensitive resin adhesive characterized in that in an apparatus, inert gas is blown from below the belt to eliminate oxygen inside the concave mold, and ultraviolet rays are irradiated from above to cure the photosensitive resin adhesive. Law.