JPH06104217B2 - UV irradiation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention applies a UV curable resin composition (hereinafter simply referred to as UV resin) to a linear body such as a glass fiber for optical transmission to irradiate UV rays. The present invention relates to an ultraviolet irradiation device for curing by curing.

[Prior Art] A conventional ultraviolet irradiator used for coating a linear resin with UV resin and irradiating it with ultraviolet rays for curing is shown in a perspective view in FIG. 5 and a plan view in FIG. An ellipsoidal cylindrical reflecting mirror (3) is provided around the ultraviolet lamp (2), and an elongated ultraviolet lamp (2) is placed at one of the two focal points of the ellipse, and at the other focal point of the ellipse. The linear object (1) of the irradiation object is placed parallel to the axis (2) of the ultraviolet lamp or is moved in the axial direction for irradiation. In this way, the ultraviolet light emitted from the ultraviolet lamp (2) is focused on the irradiation target by the elliptical reflecting mirror, so that the irradiation target can be efficiently irradiated with the ultraviolet irradiation.

[Problems to be Solved by the Invention] However, even if the UV resin is cured on the linear object to be irradiated by using the conventional ultraviolet irradiation device as described above, the ultraviolet rays are uniformly distributed around the object to be irradiated. There is a drawback that it is not irradiated and the degree of curing is not uniform.

That is, as shown in FIG. 6, the right half of the ultraviolet rays of the ultraviolet lamp (2) is irradiated to the portion of the irradiation object at a corner α, so that the irradiation amount of the ultraviolet rays is different between the irradiation object and the lamp side. However, there was a problem that UV resin could not be cured and coated in a uniform state in the circumferential direction.

[Means for Solving the Problem] The present invention has been made by paying attention to the problems of such a conventional apparatus, in which two or more ultraviolet lamps are used to irradiate an object to be irradiated with ultraviolet light from multiple directions. In addition, it is possible to cure the UV resin of the irradiation object uniformly by irradiating the irradiation object with ultraviolet rays almost uniformly around the irradiation object by using a reflecting mirror having a cylindrical structure in which a plurality of ellipses are combined. The purpose is to

The present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a plan view thereof. As shown in the figure, three UV lamps (2) are arranged at the same distance from the center of the linear object to be irradiated (1) and at the same angle in the circumferential direction, and the object to be irradiated is provided outside thereof. Position as a common focus and the position of the UV lamp as the second position.
It is equipped with a cylindrical reflector (4) that is a combination of elliptical focal points.

When the UV irradiation device with this structure is used, the UV light emitted from each UV lamp is focused on the linear body by the reflecting mirror and the UV resin is irradiated on the coating linear body. The irradiation range of the ultraviolet rays is divided and the respective ranges are efficiently irradiated, and the irradiation from all the lamps is combined and the irradiation is performed on the entire circumference of the irradiation target. Therefore, according to this apparatus, it is possible to obtain a uniform cured coating without a significant difference in the degree of curing between the lamp side and the opposite side of the object to be irradiated, which has been conventionally seen. The reflecting mirror (4) used in the device is not enough to reflect ultraviolet rays well like a reflecting mirror made of metal such as aluminum. It reflects ultraviolet rays necessary for curing but transmits heat rays (infrared rays). Material For example, on a metal plate
It is preferable to use a reflector made of a material such as a ceramic coating in which a high refractive material such as ZnS and a low refractive index material such as Nas ₃ AlF ₆ are laminated. It is possible to suppress the temperature rise due to, and it is possible to prevent the ultraviolet lamps from shortening the life due to their interaction.

3 and 4 show another embodiment of the present invention. As in Fig. 1, the linear object (1)
Book ultraviolet lamps (2) are arranged at equal distances from the center and at equal angles in the circumferential direction, and the position of the irradiated object is a common focus and the position of the ultraviolet lamp is a second focus on the outside thereof. It has a cylindrical reflector (4) that is a combination of ellipses, and the reflector (4) is centered around the irradiation target (1).
Three shield plates (5) are provided between the ultraviolet lamps radially toward the intersection of the elliptical shape.

According to this structure, it is possible to prevent heat generation (heat rays) of a large number of ultraviolet lamps (2) from being shielded by the shielding plate and mutually heating the ultraviolet lamps to shorten the life.

Of course, the reflector made of the material used in FIGS. 1 and 2 and FIG.
Better results can be obtained by using in combination with the shielding plate used in FIG.

Although the case where three ultraviolet lamps are used has been described above as an example, the same effect can be obtained by using a reflecting mirror in which elliptical shapes are combined in accordance with the number of ultraviolet lamps when the number is two or four or more. Of course there is.

UV resins to be cured by the apparatus of the present invention include urethane resins such as urethane acrylate, epoxy resins such as epoxy acrylate, polyester resins such as polyester acrylate, polybutadiene resins such as polybutadiene acrylate, and silicone resins such as silicon acrylate and their compounds. Alternatively, it contains a resin containing a part of the above UV resin.

[Example] Example 1 A urethane type UV resin was applied to a glass fiber for optical transmission by using a conventional type irradiation device and an irradiation device of the present invention as shown in FIG. 1 using three ultraviolet lamps. Then, it was irradiated with ultraviolet rays and cured to make a comparison.

The UV lamp used has an output of 80 W / cm, and the ellipse of the reflecting mirror is the major axis a = 68 mm and the minor axis b = 55 m shown in FIGS. 6 and 2.
m, that is, major axis: minor axis = a: b = 1.24: 1.00, focal length = 8
It was set to 0 mm. Also, after UV coating the glass fiber for optical transmission with an outer diameter of 125 μm, the outer diameter should be 250 μm.
V resin was applied and cured.

Take out the cured UV resin coated glass fiber for optical transmission, peel off the coating layer in the direction of BB in FIG. 6 and AA in FIG. 2, and measure the curing degree of the resin on the right and left sides. And compared. The measurement was carried out by immersing the cured resin in methyl ethyl ketone at 100 ° C. for 12 hours for extraction, and using the weight before extraction as Wo and the weight after extraction as W, the value of the following formula was used.

Curing degree = W / Wo × 100 The obtained results are shown in Table 1.

From the above results, it can be seen that the apparatus of the present invention can obtain a very uniform UV curing as compared with the conventional apparatus.

Example 2 The life of the ultraviolet lamp in the three types of ultraviolet curing apparatus of the conventional type shown in FIG. 5 and the present invention type shown in FIGS. 1 and 3 in which the output of the ultraviolet lamp and the ellipse of the reflecting mirror are the same as those of the first embodiment. Were compared. The lamp life was defined as the time until the initial irradiation dose (brightness) was reduced to 80%.

The results are shown in Table 2.

From the above results, in the case of the ultraviolet irradiation device having the structure shown in FIG. 3 in which the shielding plate is provided radially around the linear body, only one lamp is used even though a plurality of lamps are used. It can be seen that it has a long lamp life, which is almost similar to the conventional device used.

[Effects of the Invention] As described in detail above, according to the ultraviolet irradiation apparatus of the present invention, the conventional apparatus irradiates the irradiation object from one direction, while at least two ultraviolet lamps are used. Or more than that, UV rays irradiate the irradiation object from two or more directions, and the shape of the combination of elliptical shapes is such that the irradiation object position is the common focus and the ultraviolet lamps are at the respective second focus positions. Equipped with a cylindrical reflector
Moreover, since a material that reflects ultraviolet rays but transmits heat rays is used as the material of the reflecting mirror, it is possible to uniformly irradiate the linear UV resin coating with ultraviolet rays in any circumferential direction to uniformly cure the UV resin coating. It was possible to mitigate the phenomenon that the conventional cured state greatly differs depending on the circumferential direction.

Furthermore, by providing a material for the reflecting mirror and a structure in which a shielding plate that separates the lamps around the linear body is provided, it is possible to prevent the lamps from shortening their life due to mutual heating.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an ultraviolet irradiation device of the present invention, and FIG. 2 is a plan view thereof. FIG. 3 is a perspective view showing another embodiment, and FIG. 4 is a plan view thereof. FIG. 5 is a perspective view of a conventional ultraviolet irradiation device, and FIG. 6 is a plan view thereof. [Explanation of reference symbols] (1) ... Irradiation object, linear body (2) ... UV lamp (3), (4) ... Reflecting mirror (5) ... Shielding plate

Claims (3)

[Claims] 1. An ultraviolet irradiation device for irradiating a linear object (1) with ultraviolet light, wherein at least two or more ultraviolet lamps (2) are provided around the object (1). A combination of elliptical shapes which are arranged at equal distances and at equal angular positions in the circumferential direction, and on the outside of which the position of the irradiated object (1) is the common focus and the position of each ultraviolet lamp (2) is the second focus An ultraviolet irradiating device, characterized in that a cylindrical reflecting mirror (4) having a curved shape is provided, and a material that reflects ultraviolet rays and allows heat rays to pass therethrough is used. 2. An ultraviolet irradiation device for irradiating a linear object (1) to be irradiated with ultraviolet rays, wherein at least two or more ultraviolet lamps (2) are provided around said object (1). A combination of elliptical shapes which are arranged at equal distances and at equal angular positions in the circumferential direction, and on the outside of which the position of the irradiated object (1) is the common focus and the position of each ultraviolet lamp (2) is the second focus The cylindrical reflecting mirror (4) having a curved shape is provided, and the shielding plate (5) is provided between the ultraviolet lamps in a radial direction toward the intersection of the elliptical shapes of the reflecting mirror (4) with the irradiation target (1) as the center. An ultraviolet irradiation device characterized in that 3. An ultraviolet irradiation device for irradiating a linear object (1) with ultraviolet rays, wherein at least two or more ultraviolet lamps (2) are provided from the center of the object (1). A combination of elliptical shapes which are arranged at equal distances and at equal angular positions in the circumferential direction, and on the outside of which the position of the irradiated object (1) is the common focus and the position of each ultraviolet lamp (2) is the second focus Is provided with a cylindrical reflecting mirror (4) having a curved shape, a material that reflects ultraviolet rays and allows heat rays to pass therethrough, and has an elliptical shape with respect to the object (1) to be irradiated. An ultraviolet irradiation device, characterized in that a shielding plate (5) is provided between the ultraviolet lamps radially toward the intersection.