JP2005297398A - Method and apparatus for bonding precise part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bonding method for reducing the internal residual stress after curing caused by curing shrinkage regardless of an adhesive form or the like at the time of bonding of an adherend and an adhesive material using an energy curable adhesive to avoid the positional shift of a part caused by a change with the elapse of time. <P>SOLUTION: An adhesive region is filled with the energy curable adhesive so as to provide a predetermined density gradient and an adhesive curing process is changed stepwise in the adhesive region. Therefore, when the whole of the adhesive irradiated with an energy beam all at once, curing reaction is easy to start probably from the part high in the density gradient of the adhesive of the adhesive region to stepwise advance to the part low in density distribution of the adhesive region to impart a gradient to the degree of progress of the curing process. Accordingly, the preceedingly cured adhesive is cured while a curing shrinkage amount is replenished with an adjacent part having flowability to markedly reduce the occurrence of internal stress due to curing shrinkage. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method (and a joining apparatus) for joining precision parts with an adhesive, and by devising the structure of the adhesive layer and causing a time shift in the curing process in the adhesive layer, the adhesive layer It is possible to suppress the occurrence of stress inside, and to suppress the residual stress and prevent the positional shift (time shift) between the adherend and the adhesive due to the change with time, especially small optical parts, liquid crystal parts, It can be effectively used for adhesive bonding of precision parts such as electronic parts.

Various types of energy curable adhesives such as a thermosetting type and a light curable type are known as adhesives for bonding an adhesive to an adherend. These energy curable adhesives have a high reaction speed and a curing time. Since it is short and therefore efficient in the production process, it is used in various technical fields.
By the way, this energy curable adhesive causes curing shrinkage when cured, and stress is generated along with this curing shrinkage. Generally, the acrylic ultraviolet curable resin is cured and shrunk by about 5 to 10%, and the epoxy ultraviolet curable resin is about 2 to 5%, and a curing shrinkage force proportional to the amount of curing shrinkage is generated. The effect of this shrinkage on the adhesive strength is slight, but if this cure shrinkage remains as an internal stress after curing, this internal residual stress is released over time, and this residual stress changes over time. For this reason, a deviation occurs in the bonding position between the adherend and the bonded material, which may reduce the intended function of the precision assembly part and deteriorate the high-precision performance.
Various technical developments have been made to avoid this problem, and there are the following.

  The first method is described in Japanese Patent Application Laid-Open No. 2000-090481 and Japanese Patent Application Laid-Open No. 10-309801, which uses a thin and small amount of adhesive to be used (applied), and is aged over time due to temperature fluctuations. It is a method of reducing changes. However, in these methods, the bonding structure between the adherend and the bonded object is limited, and since it is indirect bonding, another part is required, and there are problems that the number of bonding points increases.

  The second method is described in JP-A-10-121013 and JP-A-07-201028, which is a method of modifying the adhesive itself, specifically, ceramic fine particles. This is a technique for reducing the time-dependent change due to temperature fluctuations, etc. by reducing the curing shrinkage of the adhesive by addition or filler addition and reducing the internal residual stress. In recent years, this adhesive has been actively developed. However, in this case, a special adhesive is required, and as the amount of the adhesive increases, the amount of cure shrinkage increases, which causes a problem that the internal residual stress increases.

The third method is described in Japanese Patent Application Laid-Open No. 09-197105. This is performed by adjusting the thickness of the bonding layer following the shrinkage of the bonding layer accompanying the curing shrinkage of the adhesive. This is a technique for reducing stress caused by shrinkage. However, this technique is basically surface bonding, the bonding structure is limited, can only reduce the stress that occurs at the interface between the adhesive that cures and shrinks and the part that does not shrink, and the adhesive after curing. Since the internal residual stress cannot be greatly reduced, it is also impossible to prevent a time lag.
As described above, in the above-described conventional technique, the stress remaining in the adhesive after curing cannot be reduced, and therefore, the time lag cannot be reduced.

Moreover, although it is not an adhesion technique, there are the following three-dimensional modeling techniques.
Japanese Patent No. 2970300 discloses a laser beam that scans in a ring shape from the approximate center of gravity of the cross-sectional shape to the outside, thereby eliminating the bias of internal stress associated with curing shrinkage and preventing deformation. However, in order to carry out the method, it is necessary to converge energy rays (laser light) corresponding to curing to a minute spot and scan concentrically from the approximate center of the adhesive, resulting in a large apparatus configuration. Not only that, but the entire bonding area is cured by micro spot scanning, so it takes a long time to cure, and it is difficult to directly apply the conventional technology in the field of 3D modeling technology to the bonding technology. Even if it is used, there is a problem that the time required for the bonding process becomes long.
JP 2000-090481 A JP-A-10-309801 JP-A-10-121013 Japanese Patent Application Laid-Open No. 07-201028 JP 09-197105 A

  The object of the present invention is to solve the above-mentioned problems all at once, and after positioning the adherend and the adhesive with high accuracy, the adhesive and the adherend are bonded with an energy curable adhesive. Using a simple device configuration to reduce the internal residual stress after curing due to curing shrinkage, and avoid misalignment of parts due to changes over time The challenge is to devise a method.

[Solution 1] (corresponding to claim 1)
Means 1 for solving the above-mentioned problem is a joining method using an energy curable adhesive, and after positioning the adherend and the adhesive with high accuracy, the energy beam is irradiated all at once to adhere to the adherend. Assuming a precision part joining method to join objects,
A substance causing a curing reaction is filled in the adhesive region with a predetermined density gradient, and the curing process of the energy curable adhesive is changed stepwise in the adhesive layer region. .
The “substance causing the curing reaction” described above is a substance that accelerates the curing reaction of the adhesive by irradiation with energy rays.
The “energy curable adhesive” means an adhesive that is cured by irradiation with energy rays such as visible light, ultraviolet rays, radiation, and X-rays.
Also, “stepwise” above means that the curing process is almost continuous and stepwise within the bonded area.

[Action]
The adhesive layer in the above-mentioned adhesion region is a material in which a substance causing a curing reaction is filled in the adhesion region with a predetermined density gradient. For this reason, when the adhesive is cured by irradiating the entire adhesive layer with energy rays all at once, the curing reaction is probable to start probabilistically from the portion where the density gradient of the substance that causes the curing reaction is high, and the curing reaction has a density. As it progresses step by step to a lower distribution, a gradient is imparted to the progress of the curing process. Therefore, when energy rays are irradiated onto the curable adhesive all at once and the curing proceeds, the number of parts that are cured simultaneously is reduced. The probability of being held is extremely high, and the adhesive that hardens in advance cures while the amount of cure shrinkage is replenished from the adjoining portion having fluidity, so that the generation of internal stress due to cure shrinkage is significantly reduced. Since such a curing process proceeds step by step in the entire adhesive layer, the residual stress is greatly reduced for the entire adhesive layer.
Therefore, the positional shift (time shift) of the bonded object with respect to the bonded object due to the temporal change of the residual stress is greatly reduced.

[Solution 2] (corresponding to claim 2)
Means 2 for solving the above-mentioned problem is a joining method using an energy curable adhesive, and after positioning the adherend and the adhesive with high accuracy, the adhesive is applied to the adherend by irradiating energy rays all at once. Assuming a precision component joining method
A material that suppresses the progress of the curing reaction of the adhesive is filled in the adhesive region with a predetermined density gradient, and the curing process of the energy curable adhesive is changed stepwise in the adhesive layer region. It is that.
The “substance that suppresses the progress of the curing reaction” is a substance that suppresses the curing reaction of the adhesive caused by energy irradiation.
Also, “stepwise” above means that the curing process is almost continuous and stepwise within the bonded area.

[Action]
The adhesive layer in the adhesive region is a material in which a substance that suppresses the progress of the curing reaction is filled in the adhesive region with a predetermined density gradient. For this reason, when the adhesive is cured by irradiating the entire adhesive layer with energy rays at once, the curing reaction is probable to be started probabilistically from a portion having a low density gradient of the substance that suppresses the progress of the curing reaction, Since it progresses step by step to a portion having a high density distribution, a gradient is given to the progress of the curing process. Therefore, when curing is progressed by irradiating energy rays to the curable adhesive all at once, the portion that is cured at the same time is reduced, and the fluidity is maintained in the adhesive in the adjacent portion of the adhesive that is cured beforehand. The adhesive that hardens in advance is cured while the shrinkage of the adhesive is replenished from the fluidly adjacent portion, so that the internal stress due to cure shrinkage is remarkably reduced. Since such a curing process proceeds step by step in the entire adhesive layer, the residual stress is greatly reduced for the entire adhesive layer.
Therefore, the positional deviation (time deviation) of the adhesive with respect to the adherend accompanying the change in the residual stress with time is greatly reduced.

[Embodiment 1] (corresponding to claim 3)
In Embodiment 1, the precision component joining method of Solution 1 described above is arranged such that the substance causing the curing reaction in the adhesive layer is inclined so that the density is highest at the center and lowest at the periphery in the adhesion region. It is to be filled with.

[Action]
Since the density of the substance causing the curing reaction in the adhesive layer is highest at the center and lowest at the periphery, the adhesive layer is cured from the center toward the periphery, and finally the periphery is cured. And when the periphery hardens, the flowable adhesive that supplements the shrinkage of the periphery is not adjacent, but there is nothing that resists the shrinkage of the periphery adhesive, so internal stress occurs in this part. There is nothing.
Therefore, the generation of the internal stress and the residual stress are effectively reduced in the entire adhesive layer.

[Embodiment 2] (corresponding to claim 4)
Embodiment 2 relates to the precision part joining method of Solution 2 above, and the density of the substance that suppresses the progress of the curing reaction in the adhesive layer is the lowest in the center of the adhesive region and the highest in the periphery. That is, it was filled with a gradient.

[Action]
Since the density of the substance that suppresses the progress of the curing reaction in the adhesive layer is the lowest at the center and the highest at the periphery, the curing of the adhesive layer proceeds from the center toward the periphery, and finally the periphery is cured. When the periphery hardens, there is no fluid adhesive that replenishes the cure shrinkage, but there is nothing that resists the shrinkage shrinkage of the peripheral adhesive, so internal stresses are not generated in this area. Absent.
Therefore, the generation of the internal stress and the residual stress are effectively reduced in the entire adhesive layer.

[Embodiment 3] (corresponding to claim 5)
Embodiment 3 relates to the above-mentioned Solution 1 and the method for joining precision parts of Embodiment 1, wherein the substance causing the curing reaction is a micro wall comprising a photoinitiator as a core substance and a capsule wall material surrounding the core substance. It is composed of capsules.

[Action]
The capsule wall material of the microcapsule is broken by irradiation with energy rays, so that a substance causing the curing reaction flows into the adhesive layer, the curing reaction is started, and before the irradiation with the energy rays for bonding and curing. In this stage, the curing reaction is not started.

[Embodiment 4] (corresponding to claim 6)
Embodiment 4 is that the substance that suppresses the progress of the curing reaction of the solution 2 and the precision part joining method of Embodiment 2 is a powder that restricts the amount of transmission of energy rays.

[Action]
Since the substance that suppresses the progress of the curing reaction is a powder that limits the amount of energy rays transmitted, the higher the density of the powder, the lower the amount of energy beam irradiation to the inside of the adhesive layer. Is slow. Therefore, a gradient is imparted to the curing rate of the adhesive layer depending on the density of the powder.

The effects of the present invention are summarized as follows for each main claim.
(1) Inventions according to claims 1 and 2 By curing with a spatial gradient in the progress of the curing process, fluidity is maintained in the adjacent portion of the adhesive to be cured, and the internal residue after curing due to curing shrinkage Stress can be reduced, and an adhesive structure with little change with time can be obtained.
Moreover, irradiation control is not performed, large-scale control and expensive equipment are not required, and it is not necessary to secure a wide installation place, so that it is easy to replace existing equipment.

(3) Inventions according to Claims 3 and 4 There is no point where the curing process progresses slower than the surroundings inside the bonded portion, and curing can be performed with a spatial gradient in the progress of the curing process. The fluidity is maintained in the adjacent portion of the adhesive, the internal residual stress after curing due to curing shrinkage can be reduced, and adhesion with little time lag can be performed.

(4) Invention according to claim 5 Filling the adhesive layer with the substance and the concentration distribution thereof by confining the photoinitiator until the start of adhesion by irradiation with energy rays by making the substance resulting from the curing reaction into microcapsules Adjustment can be performed without any trouble, and the invention according to claim 1 or claim 3 can be easily implemented.

(5) The invention according to claim 6 The invention according to claim 2 can be easily and easily carried out by filling the surface layer portion of the adhesive layer with a powder that restricts transmission of energy rays, for example, fine powder such as carbon black. The present invention according to claim 2 can be carried out at a low cost because it can be carried out and an extremely inexpensive powder can be used. Therefore, the quality and reliability of precision parts formed by bonding a plurality of objects can be remarkably improved at a low cost.

(6) The invention according to claim 8 The joining structure of the invention according to claim 8 is such that the initial deviation between the adherend and the adherend is small and the deviation with time is suppressed as much as possible. Is of high quality and the quality is not deteriorated due to the time lag, so the reliability of the quality is extremely high.

  The first embodiment will be described with reference to FIGS. 1 and 2 while comparing with the above-described conventional joining structure.

  Example 1 is a bonding structure in which an object to be bonded 1 and an adhesive 2 aligned with the object to be bonded are bonded via an adhesive layer 3 made of a UV curable adhesive, and cured at an adhesive portion. A substance 4 (hereinafter referred to as “curing reaction accelerator”) 4 causing the reaction is filled in the adhesive layer 3. The curing reaction accelerator 4 is a microcapsule having a particle diameter of 10 to 20 μm in which a liquid benzyl agent 4b is coated with a polyamide capsule wall material 4a. The filling concentration (density distribution) of the filled curing reaction accelerator 4 is maximum in the central portion of the adhesive layer 3 and lowest in the peripheral portion. The filling concentration at the central portion is approximately 20 to 30% by volume, and the filling concentration at the peripheral portion is approximately several percent by volume.

When the adhesive layer is simultaneously irradiated with ultraviolet rays with an intensity of several tens of mW / cm ² or more, the capsule wall material 4a is destroyed by the UV irradiation, and the benzyl agent 4b therein is released into the adhesive portion and penetrates. By the penetration of the benzyl agent 4b, the center portion is most cured. On the other hand, the concentration of the benzyl agent 4b is almost zero at the peripheral portion, and the curing is completed 30 to 50% later than the central portion. And the gradient of the hardening rate similar to the density gradient of the hardening reaction accelerator 4 is implement | achieved between a center part and a peripheral part.
When bonding is performed as described above, the time lag after the accelerated test due to the temperature cycle is reduced.

Next, a bonding method according to the first embodiment will be described.
The adhesive layer 3 is formed by applying the energy curable adhesive in a desired arrangement by the first applying means 8a, the first applying means operating means 9a for moving the first applying means 8a to an arbitrary position, and the control means 11. Thereafter, the second application means 8b for applying the curing reaction accelerator 4 is moved three-dimensionally to an arbitrary position by the second application means operation means 9b, and the movement of the second application means operation means 9b is controlled by the control means 11. The curing reaction accelerator 4 is applied so as to obtain a desired density gradient.

Thereafter, the relative position between the adhesive and the adherend is determined, and the energy irradiating adhesive is irradiated with a predetermined energy beam 6 from the ultraviolet irradiation means 5 from the energy irradiation means. Energy irradiation by the ultraviolet irradiation means 5 is controlled by an energy irradiation control means 7. Control of the operation and timing of the entire apparatus is performed by the control means 11.
In Example 1, a microcapsule having a particle diameter of 10 to 20 μm in which the benzyl agent 4b is coated with a polyamide capsule wall material 4a is used as the curing reaction accelerator 4. Basically, the photoinitiator is a core. A microcapsule made of a capsule wall material made of a substance that is destroyed by irradiation energy may be used. The reason why the microcapsule is used is to prevent the photoinitiator from being mixed in advance with the energy curable adhesive.

  Examples of the photoinitiator used as the core substance include, in addition to benzyl, benzophenone, mifillarzketone, 2-chlorothioxanthone, 4-diethylthioxanthone, benzoin ethyl ether, diethoxyacetophenone, benzyldimethyl ketal, 2-hydroxy-2- Methyl propiophenone, 1-hydroxycyclohexyl phenyl ketone, aromatic iodonium salt, aromatic sulfonium salt and the like can also be used.

Further, in Example 1, the capsule wall material 4a made of polyamide was used as the capsule wall material, and the capsule material was an interfacial polymerization method, an insolubilization reaction method, a phase separation method, an interfacial precipitation method, a spray drying method, a fluidized bed. Created by manufacturing methods such as law. In addition to polyamide, poly-alginate can be used as the material. And it is necessary to make the film thickness of the capsule wall material 4a as thin as possible so that it can be quickly deformed by the curing shrinkage of the energy curable adhesive.
In addition, in order to make it quickly and easily disintegrated by irradiation with energy rays such as ultraviolet rays, an additive having a photosensitizing action is added to impart photodegradability to the polymer main chain, or the main chain at the time of polymer polymerization A structure in which a carbonyl group or the like is introduced as a photosensitizing group and is easily decomposed by light is used.

  Example 1 uses a curing reaction accelerator, but Example 2 differs from Example 1 in that a substance (curing reaction inhibitor) that suppresses the progress of the curing reaction is used. And as shown in FIG. 3, the curing reaction inhibitor 41 is distributed in the upper layer part of the contact bonding layer 3, The distribution density (filling density | concentration) is the lowest in the center part, and the periphery is the highest. The filling concentration in the central portion is approximately several percent by volume, and the filling concentration in the peripheral portion is approximately 20-30% by volume. The curing reaction inhibitor of Example 2 lowers the transmittance of ultraviolet rays from the energy irradiation means, and specifically, polycarbonate resin powder having an average particle diameter of 10 to 20 μm is used. In addition, polyethylene terephthalate, polyethylene, or the like can be used as a substance that lowers the transmittance of ultraviolet rays.

  By filling the curing reaction inhibitor 41 (polycarbonate resin powder in this Example 2) as described above, curing is suppressed most at the central portion, and curing is completed 30 to 50% later than the central portion. On the other hand, at the peripheral portion, the concentration of the curing reaction inhibitor 41 is almost zero, and the curing is most accelerated. And the gradient of the hardening rate similar to the density gradient of the hardening anti-inhibitor 41 is implement | achieved between a center part and a peripheral part.

The time lag after the accelerated test due to the temperature cycle between the adherend 1 and the adhesive 2 joined in Example 2 is reduced.
As the curing anti-inhibitor, in addition to the one that lowers the ultraviolet ray transmittance in the adhesive layer used in Example 2, oxygen (in the case of radical polymerization) that delays the photochemical reaction of the adhesive can also be used. .

Since the effect of the above technique is equivalent to setting a gradient in the progress of the curing process of the adhesive, an example of experiment using a configuration capable of temporally modulating the irradiation range on the irradiation side is shown below.
The adherend 1 is an aluminum block member having a size of 25 mm □, a thickness of 5 mm, and a reference pin of φ1 at the center. The adhesive is also the same kind of member, with a size of 20 mm □, a thickness of 5 mm, and a filling hole of φ3 in the center. The relative position of the adherend and the adhesive is adjusted so that the reference pin is inserted into the filling hole as shown in FIG. 8, and the adhesive is filled around the reference pin (clearance 1 mm) in the filling hole and cured. This completes the adhesion. The adhesive used in this experiment is an acrylic UV adhesive (TB3033: required integrated light quantity 3 J / cm ² ).

Regarding the experimental method, as a conventional example, a case where UV light having a uniform intensity (50 mW / cm ² ) is irradiated onto the adhesive after filling is used, and UV irradiation as shown in FIG. 8 is performed as an experimental example of the present invention. Comparison was made by taking the case of curing with time modulation. Although the degree of the gradient of the curing process (degree of modulation) was controlled by the time modulation described above, this time the irradiation intensity (50 mW / cm ² ) and the shutter from the center at a constant speed of 1/30 mm / sec. Opened to. FIG. 9 shows the integrated light quantity of the bonding part 3b shown in the hole 3a of FIG. 8, but the modulation degree is the integrated light quantity (J / cm ² ) on the vertical axis and the part (coordinates) (cm) of the adhesive on the horizontal axis. ) And the unit can be expressed as (J / cm ³ ). In the case of uniform irradiation, the modulation degree is 0 J / cm ³ , and in this time-modulated irradiation, modulation of 15 J / cm ³ is applied. As can be seen in the figure, the integrated light quantity at each part changes with time.
The evaluation was performed by an acceleration test. As a procedure, the relative positions of the cured samples were measured with a three-dimensional measuring instrument, and the same measurement was performed after a temperature cycle test (−20 ° C. to 70 ° C., 4 hours, 10 cycles). The amount of change before and after the temperature cycle test was grasped by the measurement, and considered as a typical characteristic value of the change with time.
The results are shown in FIG. In both cases, the number of experimental samples is nine. In the conventional example, the average value is 8.4 μm and the variation (3σ) is 10.1 μm, whereas in the method of the present invention, the average value is 2.1 μm and the variation is 1.4 μm. It turns out that it suppresses minutely.

  The adherends of Examples 1 and 2 are optical bases such as glass plates, ceramic plates, and metal plates, and the adhesives are optical elements such as lenses, diffraction gratings, and mirrors, light receiving elements, light emitting elements, It can also be an optical component such as a solid-state imaging device such as a CCD.

[Other items of the example]
The energy irradiating means in the first and second embodiments includes an ultraviolet light source that emits energy rays in the curing energy band of the UV curable adhesive, an optical fiber that guides the emitted ultraviolet light to a predetermined position, and an ultraviolet curing location. A condensing lens or a diverging lens.
Since the amount of UV irradiation necessary to cure the adhesive used is known, the cure of UV curable adhesive is determined by measuring the irradiation time from the relationship of UV irradiation intensity x irradiation time = integrated light amount, This is done by comparing the amount of light with the required irradiation efficacy.

Next, a basic structure in which the adhesive portion is filled with a substance that causes a curing reaction will be further described with reference to the drawings.
FIG. 2 shows the case where the distribution density (packing concentration) at the center is the highest and the distribution density continuously decreases toward the outer periphery, but in either case of Example 1 or Example 2. Since it is sufficient if there is a gradient of the distribution density, a linear gradient may be used as shown in FIGS. 4A and 4B, and the distribution density is highest at the end as shown in FIG. 4C. Although a curved distribution may be used, the distribution shown in FIG. 2B is most preferable.
The purpose of filling the curing reaction inhibitor is to reduce the transmittance of energy rays, so the intensity of ultraviolet (energy rays) irradiation at each part is high or low (irradiation at the center of the adhesive layer in the case of full surface irradiation) It is preferable that the density distribution of the curing reaction inhibitor is made appropriate in consideration of the highest strength and the lower peripheral edge.

Concentration adjustment at the time of application | coating of the substance (curing reaction accelerator) which causes hardening reaction, or the substance (curing reaction inhibitor) which suppresses progress of hardening reaction is the adjustment of the air pressure amount by a dispenser, and the operation means for 2nd application means It can be adjusted by the moving speed of 9b.
In Example 1, the distribution density of the curing reaction accelerator 4 is spatially unevenly distributed in the adhesive layer 3 (FIG. 2). Such filling and adjustment of the distribution density are performed as follows. .
An adhesive is applied to the bonding surface of the adherend 1 by the first applying means 8a to form an adhesive layer 3 having a predetermined thickness (FIG. 5 (a)), and then inside the adhesive layer by the second applying means 8b. The curing reaction accelerator 4 is injected, and the tip end of the curing reaction accelerator 4 is moved back and forth, right and left and up and down inside the adhesive layer 3 (FIG. 5B), and the internal distribution as shown in FIG. As described above, the filling speed by the second coating means 8b is adjusted.

Further, in Example 2, the curing reaction inhibitor 41 is distributed in the upper layer part of the adhesive layer 3, and the filling of the upper layer part and the adjustment of the density distribution are the same as in Example 1 as follows. Do as follows.
The second application means 8b for applying the curing reaction inhibitor 41 is moved three-dimensionally to an arbitrary position by the second application means operation means 9b, and the movement of the second application means operation means 9b is controlled by the control means 11. Then, the curing reaction inhibitor 41 is applied so as to have a desired density gradient.

Depending on the nature and amount of the adhesive, the concentration can be adjusted by utilizing the fact that the density near the dispenser is stochastically increased only by the amount of air pressure from the dispenser.
As the order of application, in the case of surface bonding, after the energy curable adhesive is applied to the adherend, the curing reaction accelerator 4 or the curing reaction inhibitor 41 is filled in the adhesive layer 3 and the adhesive is placed. Is desirable (Fig. 5), but in the case of a filling adhesive configuration (Fig. 6) in which a gap is filled with an adhesive, or a build-up adhesive configuration (Fig. 7) in which an adhesive is built up at the corner between the adherend and the adhesive. Is filled with the curing reaction accelerator 4 or the curing reaction inhibitor 41 after placing the adhesive 2 on the adherend 1. However, in the case of the filling adhesive form shown in FIG. 6, the adhesive is filled in the center hole of the adhesive 2 to form the adhesive layer 3, and then the curing reaction accelerator 4 or the curing reaction inhibitor 41 is applied to the adhesive layer 3. It is possible to use a procedure of filling, or alternatively, the adhesive 2 is placed on the adherend in a state where the center hole of the adhesive 2 is filled, and then the curing reaction accelerator 4 or the curing reaction inhibitor 41 is filled. You can also follow the procedure.
In short, since the curing reaction accelerator 4 or the curing reaction inhibitor 41 has only to be filled with a predetermined concentration distribution at the time of starting the energy beam irradiation, the adhesive layer is formed by the procedure most suitable for the adhesive structure. The curing reaction accelerator 4 or the curing reaction inhibitor 41 may be filled.

In both the bonded portions of Example 1 and Example 2, the curing process proceeds fastest in the central portion, the progress of the curing process becomes slower toward the end portion, and the outermost end portion is cured most slowly.
Similarly, for the other bonding forms shown in FIG. 6 and FIG. 7, similarly, the curing process proceeds fastest in the central portion, the progress of the curing process becomes slower toward the end portion, and the outermost end portion cures the latest. To do.
Therefore, no internal stress is generated in the adhesive layer during the curing process of the adhesive layer, and therefore no stress remains in the interior.

1 is a perspective view schematically showing a bonding apparatus according to an embodiment of the present invention. (A) is the adhesion structure by Example 1, (b) is a distribution map which shows typically the density | concentration distribution of the hardening accelerator in Example 1, (c) is the hardening accelerator in Example 1 typically. It is an expanded sectional view shown. (A) is the adhesion structure by Example 2, (b) is a distribution map which shows typically the density | concentration distribution of the hardening inhibitor in Example 2. FIG. (A), (b), (c) is a distribution map which shows the other example of density | concentration distribution of the hardening accelerator in Example 1, Example 2, or a hardening inhibitor. These are the front views which show typically the filling process of the hardening accelerator in Example 1. FIG. (A) is a perspective view of the other joining structure by Example 1, (b) is a distribution map of the hardening accelerator in the contact bonding layer of the joining structure, (c) is sectional drawing of the joining structure. is there. (A) is a perspective view of the further another joining structure by Example 1, (b) is a distribution map of the hardening accelerator in the contact bonding layer of the joining structure, (c) is sectional drawing of the joining structure It is. These are front views which show typically the time modulation of UV irradiation in an experiment example. These are figures showing the integrated light quantity of the adhesion part 3b of FIG. These are graphs showing experimental results.

Explanation of symbols

1: Adhered object 2: Adhered object 3: Adhesive layer 3a: Hole 3b: Adhesive part 4: Curing reaction accelerator 5: Energy irradiation means 6: Energy beam 7: Energy irradiation control means 8a: First application means 8b: First 2 application means 9a: first application means operation means 9b: second application means operation means 10a: first operation control means 10b: second operation control means 11: control means 41: curing reaction inhibitor

Claims (14)

In a joining method using an energy curable adhesive, after positioning an adherend and an adhesive with high accuracy, and then irradiating energy rays all at once to adhere the adhesive to the adherend,
A precision component in which a substance causing a curing reaction is filled in the bonding region with a predetermined density gradient, and the curing process of the energy curable adhesive is changed stepwise in the bonding layer region. Joining method. In a joining method using an energy curable adhesive, after positioning an adherend and an adhesive with high accuracy, and then irradiating energy rays all at once to join the adhesive to the adherend,
A material that suppresses the progress of the curing reaction of the adhesive is filled in the adhesive region with a predetermined density gradient, and the curing process of the energy curable adhesive is changed stepwise in the adhesive layer region. Of joining precision parts.   2. The precision part bonding method according to claim 1, wherein a substance causing a curing reaction in the adhesive layer is filled with a gradient so that the density is highest at the center and lowest at the periphery in the adhesion region. Joining method.   3. The method for joining precision parts according to claim 2, wherein the density of the substance that suppresses the progress of the curing reaction in the adhesive layer is set so as to be the lowest in the center and the highest in the periphery in the adhesive region. Joining precision parts filled.   4. The method for joining precision parts according to claim 1 or 3, wherein the substance causing the curing reaction comprises a microcapsule comprising a photoinitiator as a core substance and a capsule wall material surrounding the core substance. Is a method of joining precision parts.   The method for joining precision parts according to claim 1 or 4, wherein the substance that suppresses the progress of the curing reaction is a powder that limits the amount of transmission of energy rays. In a precision component joining device that precisely positions an object to be bonded, the bonded object, irradiates energy rays all at once, and adheres the adhesive to the object to be bonded with an energy curable adhesive.
Application means for applying a substance that causes the curing reaction or a substance that suppresses the progress of the curing reaction to the energy curable adhesive, and filling the substance with a predetermined density gradient in the adhesion region. And a density gradient control means for controlling the coating means. A bonded structure of precision parts in which an adherend and an adhesive are bonded to the adherend using an energy curable adhesive,
The curing process of the energy curable adhesive proceeds in a stepwise manner in the adhesive layer region by a substance that causes a curing reaction filled with a predetermined density gradient in the adhesion region between the adherend and the adhesive. Bonding structure of precision parts joined together.   9. The precision component joining structure according to claim 8, wherein a material that causes the curing reaction is filled and joined so as to have a gradient so that the density is highest at the center and lowest at the periphery in the adhesion region. A bonded structure of precision parts in which an adherend and an adhesive are bonded to the adherend using an energy curable adhesive,
The curing process of the energy curable adhesive proceeds in a stepwise manner in the adhesive layer region by a substance that suppresses the curing reaction filled with a predetermined density gradient in the adhesion region between the adherend and the adhesive. Bonding structure of bonded precision parts.   The precision part joining structure according to claim 10, wherein a substance is provided so as to have a gradient so as to have the lowest density at the center and highest at the periphery in the adhesion region, and is filled with a substance that suppresses the progress of the curing reaction.   10. The precision component according to claim 8, wherein the substance that causes the curing reaction is a microcapsule including a capsule wall material that uses a photoinitiator as a core substance and surrounds the core substance. Junction structure.   The capsule wall material of the microcapsule is broken by irradiation of energy rays, and the core material flows out to obtain a capsule wall material, and a curing reaction is started and bonded. The precision part joining structure according to claim 13.   12. The precision component joining structure according to claim 10, wherein the substance that suppresses the progress of the curing reaction is a powder that restricts a transmission amount of energy beam irradiation.