JPH03198235A - Method for adhering optical disk member - Google Patents

Abstract

PURPOSE:To improve the durability of the adhesive power of respective members by irradiating a UV curing type adhesive agent through a filter which cuts <=290nm wavelength, thereby curing the adhesive agent. CONSTITUTION:An outer peripheral spacer 6 and an inner peripheral spacer 7 are disposed on a substrate 4 and the substrates are superposed by disposing the recording surfaces on the inner side. The UV curing type adhesive agent 5 is applied in the form of a ring between them. A tempered glass plate 10 having the transmission spectra to cut <=290nm wavelength is placed on the substrate 4 and further 1kg weight is put thereon to uniformly spread the adhesive agent 5. The exit part of an optical fiber 1 led from a UV spot irradiating device 13 is held on the upper part of the substrate 4 and while the spotty UV ray 2 is moved along the part coated with the adhesive agent through the glass plate 10, the adhesive agent 5 is cured. The adhesive agent 5 is cured to a uniform state and the durability of the adhesive power is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive method for bonding members of an optical disk by curing an ultraviolet curable adhesive by irradiating it with ultraviolet rays.

[Conventional technology]

Conventionally known methods for adhering optical disk members using ultraviolet curing adhesives include wavelengths of 290 nm or less, and approximately 3.
Using a mercury xenon lamp or the like having an energy distribution peak around 60n-, ultraviolet light 2 from an optical fiber 1 guided from an ultraviolet spot light irradiation device 13 or the like is passed through a substrate 4 on which a load 3 is placed, as shown in Fig. 1O. By irradiating it, the ultraviolet curable adhesive 5 is cured to bond the substrate 4 and the outer circumferential spacer 6 or the substrate 4 and the inner circumferential spacer 7, or as shown in FIG. By irradiating ultraviolet rays 2 from the optical fiber 1 from above the hub 9, the ultraviolet curing adhesive 5 is
The substrate 4 and the hub 9 were bonded together by curing.

However, in this method of using a mercury-xenon lamp, if each member of the optical disk, such as the substrate 4, outer circumferential spacer 6, inner circumferential spacer 7, hub 9, etc., is made of epoxy resin, polycarbonate resin, etc., the irradiated ultraviolet rays may cause deterioration. However, the intensity of the ultraviolet light transmitted through these members changes, resulting in insufficient and uneven curing of the ultraviolet curable adhesive 5, resulting in a decrease in the durability of the adhesive force.

In order to fully cure the UV-curable adhesive, it is possible to extend the UV irradiation time, but this increases the time required to manufacture optical discs, reducing productivity, and also increases the heat generated by the UV irradiation. There is a possibility that there will be an impact.

[Problem to be solved by the invention]

The object of the present invention is to bond each member of the optical disc without deteriorating it without prolonging the manufacturing time of the optical disc, and to uniformly cure the UV-curable adhesive to increase the adhesive strength of each member. The purpose is to improve the durability of

[Means to solve the problem]

The present invention was completed in order to solve the above-mentioned problems, and includes a filter that cuts wavelengths of 290 nm or less, such as Corning's 0313 chemically strengthened glass or Toshiba colored glass filter's ultraviolet transmission filter U. V
-29 or soda-lime glass or the like to cure the ultraviolet curable adhesive and bond each member of the optical disk. More details will be described in the Examples below.

[Example 1] As shown in FIG. 1, a recording film 8 was formed by sputtering on the guide groove forming surface side of a disc-shaped substrate 4, which had guide grooves formed on one side by injection molding polycarbonate. I created two discs. Place one of the disks on a turntable with the recording film forming side facing up, and while rotating, apply ultraviolet curing adhesive Ll-9785 manufactured by Nippon Loctite Co., Ltd. to the inner and outer peripheries of the substrate 4. It was applied in a ring shape. An outer circumferential spacer 6 and an inner circumferential spacer 7 are placed on the adhesive-coated portion of this substrate, and the other disk coated with adhesive is stacked on top of them with the recording film forming side facing inside, as shown in FIG. It is arranged in an air sand inch structure.

On this substrate 4, a plate having a thickness of 1.2 m and having a transmission spectrum that cuts wavelengths of 290 nm or less as shown in FIG.
A 0313 chemically strengthened glass plate manufactured by Corning Co., Ltd. (m) was placed on top of the glass plate, and a stainless steel Ikg weight as shown in Fig. The curing UV-curable adhesive was spread evenly.

The outer diameter of the weight shown in FIG. 3 is smaller than the inner diameter of the adhesive-applied portion on the outer periphery, and the inner diameter is larger than the outer diameter of the adhesive-applied portion on the inner periphery.

Next, as shown in FIG. 4, the output part of the optical fiber 1 guided from the ultraviolet light beam 7) light irradiation device HLS200U13 manufactured by HOYA Co., Ltd. is placed on the top of the substrate 4 arranged in an air sandwich structure using appropriate means. The ultraviolet curable adhesive 5 was cured while the spot-shaped ultraviolet ray 2 was moved along the adhesive application area through a 0313 chemically strengthened glass plate 10 manufactured by Corning.

This ultraviolet curable adhesive is completely cured with an integrated light intensity of 1.5 J/cmz or more, and the irradiation intensity of the ultraviolet rays irradiated from the four-branch fiber of the ultraviolet spot light irradiation device is 1.2 W/cm on the adhesive surface. The irradiation area is φ3
It is mm2. Therefore, if the application width of the ultraviolet curable adhesive is 3 mm, the time for irradiating this application area will be 1.3 seconds.

Of the 4-branched fibers, one is used for the inner circumference and three are used for the outer circumference, and the UV-curable adhesive is applied at a radius of 13 mm from the center on the inner circumference and at a radius of 63 mm from the center on the outer circumference. If the width is 3+y+n+, the time to complete irradiation is approximately 35 seconds on the inner circumference and approximately 57 seconds on the outer circumference.
seconds.

Corning 03 that cuts wavelengths below 290 nm
13 When a polycarbonate substrate is irradiated with ultraviolet rays through a chemically strengthened glass plate, the irradiation time of the ultraviolet rays and the intensity change of the transmitted ultraviolet rays are shown in FIG. As seen in this figure, there is no change in intensity at all, so the optical discs can be bonded together under the above-mentioned irradiation conditions.

For the optical disc 1 (Hll) with the air sand inch structure created in this way, 5 sets were used for initial adhesion measurement, and the other 5 sets were left in an environment of 75°C and 85% RH for 2000 hours. The measurement results are shown in Table 1 as Example 1.

/ [Example 2] Two substrates 4 were prepared, each having a recording film 8 formed by sputtering on the guide groove forming side of a disc-shaped substrate having a guide groove formed on one side by injection molding polycarbonate. A set of optical disks as shown in FIG. 6 was prepared by bonding two substrates with the recording film forming side facing inside using a hot melt adhesive 11. This 1 m optical disk was placed on a turntable, and while it was being rotated, an ultraviolet curable adhesive Ll-9785 manufactured by Nippon Loctite Co., Ltd. was applied in a ring shape to the inner periphery of the substrate surface. On top of this optical disc is an insert molded hub HUB-0 manufactured by Nitto Chemical Industry Co., Ltd. whose periphery is made of polycarbonate resin.
3-3F9 is installed, and the plate thickness is 1.3F9, which has a transmission spectrum that cuts wavelengths of 290 nm or less as shown in FIG.
A 2 mm soda-lime glass plate was placed on it, and the glass plate was pressed using a hub pressing jig 12 as shown in FIG.
While pressing with a pressing force of 300 g, as shown in FIG. 7, the output part of the optical fiber 1 guided from the ultraviolet spot light irradiation device HLS200U13 manufactured by HOYA Co., Ltd. is held on the upper part of the hub using appropriate means, The ultraviolet curing adhesive 5 was cured while a spot of ultraviolet light 2 was moved along the adhesive-applied area through the soda-lime glass plate 10.

This ultraviolet curable adhesive is completely cured with an integrated light intensity of 1.5 J/cn+2 or more, and the irradiation intensity of the ultraviolet rays irradiated from the four-branch fiber of the ultraviolet spot light irradiation device is 1.2 W/cm on the adhesive surface. ”The irradiation area is φ31WII+2. Therefore, if the application width of the ultraviolet curable adhesive is 3 mm, the time to irradiate this application area is only 1.3 sec.Ultraviolet curable adhesive If the adhesive application position is set at a radius of 11 mm from the center and the application width is set to 31 mm, the time to complete irradiation will be about 7 seconds.

When the polycarbonate resin part of the insert-molded hub is irradiated with ultraviolet rays through a soda-lime glass plate that cuts wavelengths of 290 nm or less, the resin does not deteriorate, so the change in intensity of the UV rays that passes through the UV irradiation time is 5 As shown in the figure, there is no change at all, so
The hub can be bonded under the above-mentioned irradiation conditions.

For the 10 sets of optical discs created in this way, 5
One set was used for measuring the initial adhesive strength between the optical disk and the hub, and the other five sets were used for measuring the adhesive strength after being left in an environment of 85° C. and 85% RH for 2000 hours. The measurement results are shown in Table 2 as Example 2.

[Comparative Example 1] In the same manner as in Example 1, a disk arranged in an air sand inch structure as shown in FIG. 1 was prepared. On top of this disk, a 1kg piece of stainless steel as shown in Figure 3 is placed.
A weight was placed on the substrate to uniformly spread the uncured ultraviolet curable adhesive applied between the substrate and the spacers on the inner and outer peripheries.

Next, as shown in FIG. 10, the output part of the optical fiber 1 guided from the ultraviolet spot light irradiation device HLS200U13 manufactured by HOYA Co., Ltd. is placed on the top of the substrate 4 arranged in an air sand inch structure using appropriate means. The ultraviolet curing adhesive 5 was directly cured while the spot-shaped ultraviolet ray 2 was moved along the adhesive-applied area.

When a polycarbonate substrate is directly irradiated with ultraviolet rays without cutting off light with a wavelength of 290 nm or less, the change in the intensity of the ultraviolet rays transmitted through the substrate with respect to the irradiation time attenuates with time, as shown in FIG.

Therefore, in order to obtain the same cured state as in Example 1,
The time required to irradiate the applied area is 1.5 seconds,
Of the 4-branched fibers, 1 year is used for the inner circumference and 3 are used for the outer circumference, and the UV-curable adhesive is applied at a radius of 13I from the center on the inner circumference and a radius of 6I from the center on the outer circumference.
When the coating width is 3 mm, it takes about 41 seconds to complete the irradiation on the inner circumference and about 66 seconds on the outer circumference, making the manufacturing time longer than in Example 1.

On the other hand, the adhesion strength was measured for 10 sets of air sand inch optical discs that were produced by irradiating the discs for the same irradiation time as in Example 1. Of these, 5 sets were used for initial adhesion measurement, and the other 5 sets were placed at 75°C and 85% RH for 200°C.
After being left for 0 hours, it was used for measuring adhesive strength. The results are shown in Table 1 as Comparative Example 1.

[Comparative Example 2] In the same manner as in Example 1, a disk arranged in an air sand inch structure as shown in FIG. 1 was prepared. A quartz glass plate with a thickness of 1.2 m, which has a transmission spectrum that allows light with a wavelength of 290 nm or less to pass through, as shown in Figure 9, is placed on top of this disk, and then a quartz glass plate as shown in Figure 3 is placed on top of this quartz glass plate. A load of 1 kg was placed on a stainless steel plate as shown in Figure 1 to uniformly spread the uncured ultraviolet curable adhesive applied between the substrate and the spacers on the inner and outer peripheries.

Next, as shown in FIG. 4, the output part of the optical fiber 1 guided from the ultraviolet spot light irradiation device HLS200U13 manufactured by HOYA Co., Ltd. is placed on the upper part of the substrate 4 arranged in an air sandwich structure using appropriate means. The ultraviolet curing adhesive 5 was directly cured while the spot-shaped ultraviolet ray 2 was moved along the adhesive application area through the quartz glass plate 10.

When a polycarbonate substrate is irradiated with ultraviolet rays through a quartz glass plate, the change in the intensity of the ultraviolet rays transmitted through the substrate with respect to the irradiation time attenuates with time, as shown in FIG. Therefore, in order to obtain the same cured state as in Example 1, it is necessary to irradiate the coated part for 1.5 seconds, and one of the four-branched fibers is placed on the inner circumferential part, and three
If a book is used on the outer periphery, and the application position of the ultraviolet curing adhesive is 13 mm + radius from the center on the inner periphery, and a radius of 63 IIIOI from the center on the outer periphery, and the application width is 3 mm, the time to complete irradiation will be on the inner periphery. It takes about 41 seconds for the outer circumferential part, and about 66 seconds for the outer peripheral part, which makes the manufacturing time longer than in Example 1.

On the other hand, the adhesion strength was measured for 10 sets of air sand inch optical discs that were produced by irradiating the discs for the same irradiation time as in Example 1. Of these, 5 sets were used for initial adhesion measurement, and the other 5 sets were placed at 75°C and 85% RH for 200°C.
After being left for 0 hours, it was used for measuring adhesive strength. The results are shown in Table 1 as Comparative Example 2.

[Comparative Example 3] A set of optical discs as shown in FIG. 6, which were prepared in the same manner as in Example 2, were prepared. Place this set of optical discs on a turntable, rotate them, and place them on the inner periphery of the board.
Ultraviolet curing adhesive Ll manufactured by Nippon Loctite Co., Ltd.
-9785 was applied in a ring shape. On top of this optical disc, Nitto Chemical Industry Co., Ltd. (which is surrounded by polycarbonate resin)
Install the insert molded hub HUB-03-3F9 manufactured by Co., Ltd., and use the hub pressing jig 12 as shown in Fig. 11.
While pressing with a pressing force of 300g,
As shown in the figure, the output part of the optical fiber 1 guided from the ultraviolet spot light irradiation device HLS200U13 manufactured by HOYA Co., Ltd. is held on the upper part of the hub using appropriate means, and it is placed in a spot shape along the adhesive application area. The ultraviolet curing adhesive 5 was cured while moving the ultraviolet vA2.

When an insert-molded polycarbonate resin part is irradiated with ultraviolet rays, the change in the intensity of the ultraviolet rays transmitted through the resin part with respect to the irradiation time attenuates with time, as shown in FIG. Therefore, in order to obtain a cured state similar to that in Example 2, it is necessary to irradiate the applied area for 1.5 seconds, and the application position of the ultraviolet curable adhesive must be applied at a radius of 11 m.
If m is the coating width and the coating width is 311III+, it takes about 9 seconds to complete the irradiation, which makes the manufacturing time longer than in Example 2.

On the other hand, the adhesive force was measured for 10 sets of optical discs that were created by irradiating the same irradiation time as in Example 2.

Of these, 5 sets were used to measure the initial adhesion between the optical disk and the hub, and the other 5 sets were stored at 85°C and 85% RH for 200°C.
After being left for 0 hours, it was used to measure the strength of first appearance. The results are shown in Table 2 as Comparative Example 3.

[Comparative Example 4] A set of optical discs as shown in FIG. 6, which were prepared in the same manner as in Example 2, were prepared. Place this set of optical discs on a turntable, rotate them, and place them on the inner periphery of the board.
Ultraviolet curing adhesive Ll manufactured by Nippon Loctite Co., Ltd.
-9785 was applied in a ring shape. On top of this optical disc, Nitto Chemical Industry Co., Ltd. (which is surrounded by polycarbonate resin)
An insert molded hub HUB-03-3F9 manufactured by Co., Ltd. was installed, and a 1.2 mm thick quartz glass plate with a transmission spectrum that also passes light with a wavelength of 290 nm or less as shown in Figure 9 was placed on it. While pressing with a pressing force of 300 g using a hub pressing jig 12 as shown in FIG. 7, as shown in FIG. The ultraviolet ray curing adhesive 5 was cured while the hub was held on the upper part of the hub using an appropriate means and a spot of ultraviolet ray 2 was moved along the adhesive application area through the quartz glass plate 10.

When the polycarbonate resin portion of the insert-molded hub is irradiated with ultraviolet rays through the quartz glass plate, the change in the intensity of the ultraviolet rays transmitted through the resin portion with respect to the irradiation time attenuates with time, as shown in FIG. 8. Therefore, in order to obtain the same cured state as in Example 2, it is necessary to irradiate the applied part for 1.5 seconds, and if the application position of the ultraviolet curable adhesive is set at a radius of 11 mm from the center, the time required to complete the irradiation is 1.5 seconds. It takes about 9 seconds, which makes the manufacturing time longer than in Example 2.

On the other hand, the adhesive force was measured for 10 sets of optical discs that were created by irradiating the same irradiation time as in Example 2.

Of these, 5 sets were used to measure the initial adhesion between the optical disk and the hub, and the other 5 sets were stored at 85°C and 85% RH for 200°C.
After being left for 0 hours, it was used for measuring adhesive strength. The results are shown in Table 2 as Comparative Example 4.

〔Effect of the invention〕

As described above, in the method for adhering each member of an optical disc according to the present invention, since ultraviolet rays are irradiated through a filter that cuts wavelengths of 290 nm or less, each member of an optical disc can be bonded by the irradiated ultraviolet rays without prolonging the manufacturing time of the optical disc. The durability of the adhesive strength of each member can be improved without deteriorating the member.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of an optical disc with an air sand inch structure, Figure 2 is the ultraviolet transmission spectrum of Corning 0313 chemically strengthened glass plate or soda lime glass plate, and Figure 3 is the transmission spectrum of stainless steel. 4 is a partial cross-sectional side view of an optical disk assembly apparatus using the method of adhering each member of an optical disk according to the present invention, and FIG. 5 is a 031 weight manufactured by Corning Co., Ltd.
3. A graph of the UV irradiation time and the strengthening change of the transmitted UV rays when UV rays are irradiated onto a polycarbonate substrate through a chemically strengthened glass plate or a soda lime glass plate.
Alternatively, a graph of the UV irradiation time and intensity change of the transmitted UV rays when UV rays are irradiated onto the polycarbonate resin portion of the insert molded hub. Figure 6 is a cross-sectional view of an optical disk having a structure bonded together using a hot-melt adhesive. , FIG. 7 is a side view showing a part of the optical disc hub bonding device according to the method of bonding each member of the optical disk according to the present invention in cross section, and FIG. 8 is the ultraviolet irradiation time when the polycarbonate substrate is directly irradiated with ultraviolet rays. A graph of the intensity change of the ultraviolet rays that passes through the quartz glass plate, or a graph of the intensity change of the ultraviolet rays that pass through the polycarbonate resin part of the insert molding hub. A graph of the UV irradiation time and the intensity change of the UV rays transmitted when UV rays are directly irradiated, or the UV irradiation time and the UV rays transmitted when the polycarbonate resin part of the insert molding hub is irradiated with UV rays through a quartz glass plate. Fig. 9 is a graph of the intensity change of the quartz glass plate, Fig. 10 is a side view partially showing a cross section of an optical disc assembly apparatus according to the conventional method, and Fig. 11 is an optical disc according to the conventional method. FIG. 3 is a partially sectional side view showing a part of the hub bonding device for use in the present invention. 1: Optical fiber 2: Ultraviolet light 3: Load
4: Substrate 5: Ultraviolet curing adhesive 6: Outer spacer 7: Inner spacer 8: Recording film 9: Hub 10: Corning 0313 chemically strengthened glass plate, soda lime glass plate, or quartz glass plate 11: Hot melt Mold adhesive 12: Hub pressing jig 13: Ultraviolet spot light irradiation device 1st rXJ 6 outer periphery spacer

Claims (1)

[Claims] A method for bonding optical disk members using an ultraviolet curable adhesive, characterized in that the ultraviolet ray curable adhesive is cured by irradiating ultraviolet rays through a filter that cuts wavelengths of 290 nm or less. Method.