JPS62293275A - Adhering structure of hologram disk - Google Patents

Abstract

PURPOSE:To obtain sufficient adhering strength without lefting bubbles in an exposure part in case of sticking a resin plate whose surface is hologram- exposed to a protecting resin plate by forming a means for freeing discharged bubbles by the flow of adhesives. CONSTITUTION:A hologram disk 14 is constituted by sticking a resin plate (cover plate) 12 to a resin plate (dry plate) 11 through adhesives 13. The resin plate 11 is provided with rugged parts 16, 17 connected to a hologram exposure part 15 in the circumferential direction and the resin plate 12 is provided with rugged parts 20, 21 connected in the circumferential direction oppositely to the rugged parts 16, 17. A through-hole-like bubble guiding part 22 connected to the rugged parts and a ring-groove-like bubble guiding part 23 are formed at least on one resin plate 12. At the time of sticking both the resin plates, the adhesives 13 slowly flows in the right direction, fine bubbles mixed in the adhesives 13 and collected near the center are moved to the guide part 22 and the peripheral bubbles are moved to the guide part 23, so that no bubble is left on the exposure part 15.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Summary] The present invention provides a first resin plate whose surface has been subjected to hologram exposure, and a second resin plate for protecting the exposed area, which is attached via an adhesive. The purpose is to ensure that no air bubbles remain in the exposed area when bonding, and that sufficient adhesive strength is obtained. This objective is achieved by providing a surface roughening section and providing a means to release air bubbles that are discharged into the surface roughening section by the flow of adhesive when the two resin plates are bonded together.

[Industrial application field]

The present invention relates to an adhesive structure for a hologram disk.

A hologram disk is constructed by adhering a cover plate for protecting the exposed portion to a dry plate whose surface has been subjected to holographic exposure via a two-component adhesive. This hologram disc is
Like other mechanical parts, there is a strong demand for lightweight and low-cost products, and dry plates and cover plates are being replaced from conventional glass plates to ones made of resins such as acrylic. Therefore, there is a need for a structure that can take advantage of the characteristics of the resin and maintain and improve adhesive strength.

[Conventional technology]

FIG. 5 shows a conventional hologram disk bonding process.

In the figure, l is the first resin plate (dry plate), 2 is the second resin plate (
cover plate). The resin plate 1 is shown in FIG. 6 (al, (b)
As shown in detail in FIG. It is a plate-shaped object having the same external shape as the plate 1.

The hologram disk is constructed by bonding a cover plate 2 over the exposed portion of a dry plate 1 with an adhesive. Next, the method of bonding will be explained with reference to FIG.

For bonding, first the dry plate 1 is placed on the workbench 6 with the exposure section 3 facing upward.

Next, after applying a predetermined amount of the two-component adhesive 7 to the left end of the dry plate l, the cover plate 2 is tilted as shown in the figure to bring it close to the dry plate l, and the cover plate 2 is supported by the left end as indicated by the arrow. Adhesion is performed by tilting and pressing in the clockwise direction shown.

In this case, as the cover plate 2 falls down, the adhesive 7
While flowing to the right, it fills the surface roughening portions 4 and 5 and is uniformly stretched over the other flat areas. Therefore,
The adhesive strength is improved due to the surface roughening effect and the sufficient thickness of the adhesive at the surface roughening portion 4.5.

[Problem that the invention seeks to solve]

However, in the conventional adhesive structure as described above, since air is drawn in during the adhesive stretching process, minute air bubbles are scattered everywhere including the exposed areas, resulting in a decrease in adhesive strength. In addition, bubbles especially in the exposed area pose a fatal problem for hologram disks, such as a decrease in laser light efficiency.

In the conventional structure, such scattered air bubbles have no place to escape and are only visible visually after completion of adhesion, so there is nothing that can be done about it.

[Means for solving problems]

The present invention provides a hologram disk adhesive structure that can solve the above-mentioned problems, and the principle thereof is shown in FIG.

In Fig. 1, 11 is the first resin plate (dry plate), 12 is the second resin plate (cover plate), and 13 is the 2 resin plate for bonding both resin plates.
It is a liquid adhesive.

The hologram disk 14 is attached to the first resin plate 11 with a second
It is constructed by bonding resin plates 12 with an adhesive 13.

The resin plate 11 includes, on the surface facing the resin plate 12, an exposed portion 15 and a surface roughened portion 16.17 formed at a position away from the exposed portion 15 and continuous in the circumferential direction.

The resin plate 12 also has a surface roughening portion 2 on the surface facing the resin plate 11, which faces the surface roughening portions 16 and 17 and continues in the circumferential direction.
It has 0.21.

Furthermore, at least one of the resin plates 12 is provided with a bubble guide portion 22, 23 that communicates with the surface roughening portion. The bubble guiding part 23 is exemplified as having a ring groove shape that is deeper than the surface roughening part 21 and communicating with the surface roughening part 21, and the bubble guiding part 22 is in the form of a through hole that is communicating with the surface roughening part 20. is exemplified.

[Effect]

When bonding both resin plates, as shown in FIG. 1, the resin plate 12 is pressed down on the resin plate 11 coated with a certain amount of adhesive 13 as shown by the arrow. In this case, the adhesive 13 slowly flows to the right,
In this process, among the microbubbles mixed in the adhesive, those near the center move toward the bubble guide section 22, and those near the outer periphery move toward the bubble guide section 23. Therefore, the bubbles are completely guided out of the exposed area 15 where their presence is not allowed.
There are no remaining bubbles in the exposed area.

Further, since the deep bubble guide portion 23 on the outer circumferential side is provided in an unnecessary portion that is cut at the time of production, the strength of the disk will not be reduced.

〔Example〕

The present invention will now be described in detail with reference to FIGS. 2 to 4.

FIG. 2 is a cross-sectional view showing a hologram disk according to the present invention. In the figure, 11 is a first resin plate (dry Fi) with holographic exposure at a predetermined position on the surface, and 12 is a second resin plate (cover board), 13 is a two-component adhesive for bonding both resins. The hologram disk 14 has a dry plate 11 and a cover plate 12.
are bonded together with an adhesive 13.

As shown in detail in FIGS. 3(a) and (bl), the dry plate 11 has an exposed portion 15 formed on the surface facing the cover plate 12, and a center portion and an outer peripheral portion at positions away from the exposed portion 15. The dry plate 11 has a ring groove-shaped surface roughened portion 16' and 17 which are continuous in the circumferential direction. The hole 18 communicates with the surface roughened portion 16' via the connection #24 and penetrates the dry plate 11, and the ring-shaped groove 19 communicates with the surface roughened portion 17 on the outside and connects between the nuclei. It is formed deeper than the roughened portion 17.

In addition, the cover plate 12 has a surface roughening portion 16' on the surface facing the dry plate 11, as shown in detail in FIGS.
It is provided with ring groove-shaped surface roughening parts 20' and 21 opposite to 17. This cover plate 12 is provided with a hole (bubble guide part) 22 opposite to the hole 18 and a ring-shaped groove (bubble guide part) 23 opposite to the ring-shaped groove 19. The hole 22 is connected to the surface roughened portion 20' through a communication groove 25, and is connected to the cover plate 1.
2, and the ring-shaped groove 23 communicates with the surface roughened portion 21 on the outside and is formed deeper than the internuclear roughened portion 21.

When bonding both resin bodies, as in the past, a certain amount of adhesive 13 is applied.
The cover plate 12 is tilted and brought close to the dry plate 11 coated with the adhesive, and the cover plate 12 is pressed and bonded while tilting it down using one end as a fulcrum. In this case, the adhesive is slowly stretched and flows from the fulcrum side to the opposite side. During this stretching process, the air bubbles that are drawn into the hole 18, 22 near the center
In addition, near the outer periphery, the bubbles are guided into the ring-shaped grooves 19 and 23, and are completely removed from the exposed area 15, where the generation of bubbles is absolutely not allowed.

Also, during this bonding, the adhesive 13 is also applied to each groove-like surface roughening part.
flows in, increasing the thickness of the adhesive layer in this area, and also suppressing the generation of air bubbles in this adhesive layer.In conjunction with the surface roughening effect of the surface roughening section, the adhesive strength is sufficient to withstand high-speed rotation. can get.

Furthermore, since the deep ring-shaped groove 23 on the outer circumferential side is provided in an unnecessary part that is cut at the time of production (range A in FIG. 2 is the product part), it does not reduce the strength of the disk.

In the above description, the bubble guide portions are provided on both resin plates, but the bubble guide portions may be provided on only one of the resin plates. In addition, if a hole-shaped bubble guiding part is provided in the center of both resin plates as in this example, these holes can be used for positioning the two resin plates, and the holes can be used to align the two resin plates. It is possible to completely match the surface roughening portions, etc.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to completely eliminate air bubbles from the exposed area, which is the heart of the hologram disk, and furthermore, it is possible to obtain a further improved adhesive strength. It is possible to obtain a hologram disk that can sufficiently withstand high-speed rotation for a long time.

[Brief explanation of drawings]

Figure 1 is a diagram showing the principle of the present invention. Figure 2 is a sectional view showing a hologram disk according to an embodiment of the present invention. □ Figure 3 (al and Figure 3 fb) is a plan view and side view showing the structure of the dry plate. Figure 4 (ta) and Figure 4 (fb) are a plan view and side sectional view showing the structure of the cover plate, Figure 5 is an explanation of the conventional hologram disk bonding process, a clear diagram, and Figure 6 (ta). and FIG. 6 fb) are a plan view and a side cross-sectional view showing the structure of a conventional hologram 1 and a dry plate for discs. In the figure, 11 is a first resin plate (dry plate), 12 is a second resin plate (cover). 13 is a two-component adhesive, 14 is a hologram disk, 15 is an exposed part, 16.16', 17.20.20'21 is a surface roughening part, 18.22 is a hole (bubble induction part) , 19.23 is a ring-shaped groove (bubble guide part).

Claims (1)

[Claims] 1. A hologram disk in which a second resin plate for protecting the exposed area is adhered to a first resin plate whose surface has been subjected to hologram exposure through an adhesive, in which each of the resin plates is Groove-shaped surface roughening portions continuous in the circumferential direction are provided at positions adjacent to the exposed portions of the opposing surface so as to face each other, and at least one of the resin plates is provided with the surface roughening portions. An adhesive structure for a hologram disk, characterized in that a bubble guiding part is provided that communicates with the part. 2. The bonding structure for a hologram disk according to claim 1, wherein the bubble guiding portion is a ring-shaped groove deeper than the surface roughening portion. 3. The hologram disk adhesive structure according to claim 1, wherein the bubble guide portion is a hole penetrating the resin plate. 4. The surface roughening portion is formed at the center portion and the outer peripheral portion of each resin plate, the air bubble guiding portion at the center portion is a hole, and the air bubble guiding portion at the outer peripheral portion is a ring-shaped groove. Adhesive structure of hologram disk.