JPH05331438A - Fluorescent adhesive, method for inspecting coating state of adhesive and apparatus for inspection - Google Patents

Abstract

PURPOSE:To obtain a fluorecent adhesive, comprising a fluorescent agent and capable of discriminating the acceptance or rejection of the coating state by image processing and useful as electrical and electronic apparatus products, etc. CONSTITUTION:The fluorescent adhesive 1 is obtained by including preferably 0.1-1 pt.wt. fluorescent agent such as Rhodamine in an adhesive such as a urethane acrylate-based ultraviolet curing adhesive. The coating state of the adhesive is preferably inspected by irradiating a material 2 which is coated with the fluorescent adhesive 1 containing the fluorescent agent for inspection with ultraviolet rays.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent adhesive for surely and efficiently inspecting an adhesive application state. Furthermore, the present invention relates to an adhesive application state inspection method and an inspection apparatus.

[0002]

2. Description of the Related Art In recent years, there have been remarkable changes in electronic equipment products such as lightness, thinness, shortness, miniaturization, multifunction, high quality, and low price. Therefore, in the past, automation of the manufacturing process has been promoted in order to increase the production amount and reduce the labor cost. For example, even in the advanced process that exceeds the limit of human ability, the manufacturing process can be performed in any situation. Automation is being promoted more and more.

By the way, the adhesive assembly method is widely used for assembling products in various industrial fields because it requires no parts for assembly and has high productivity.
Adhesives are widely used not only for adhesive assembly, but also for applications such as coating and sealing. As the industrial structure has changed from high-volume production to high-mix, low-volume production, the demand for highly functional adhesives has increased. Those with excellent adhesion strength and adhesion reliability, those with a high adhesion speed,
For example, those having special functions such as electrical, thermal, optical and biocompatibility are added.

[0006] Of the miniaturized and complicated bonding and assembling steps, the steps of applying and curing the adhesive are still being automated. In addition, in the inspection process of confirming the coating state, it is often the case that inspections that exceed the limits of human visual ability are required due to the miniaturization and high density of products. Therefore, if the inspection process can be automated, it is expected that workability and productivity can be greatly improved.

However, even if an adhesive coating state is to be processed by image processing, there is a problem that the efficiency of inspection is poor, and complete automation has not been achieved. This is because it is often difficult to accurately capture the image information and perform accurate image processing due to the color of the adherend.

[0006]

Therefore, the present invention has been proposed in view of such circumstances, and provides a fluorescent adhesive capable of accurately and efficiently inspecting the coating state of the adhesive. To provide an inspection method that makes it easy to visually check the application state of the adhesive, such as the application position and the application amount of the adhesive, by using the adhesive, and an inspection device that automates the inspection of the adhesive application state. The purpose is to provide.

[0007]

The inventor of the present invention has made various studies in order to achieve the above object. As a result, it has been found that if a fluorescent agent is mixed in the adhesive, it can be easily made visible by irradiation with ultraviolet rays, and by applying image processing to it, the application position and application amount can be confirmed. Came to get. The present invention has been completed based on such findings.

That is, the fluorescent adhesive of the present invention is characterized by containing a fluorescent agent. The inspection method of the present invention is characterized by irradiating an object to be inspected coated with a fluorescent adhesive containing a fluorescent agent with ultraviolet rays. Furthermore, the inspection device of the present invention comprises a light source for irradiating an object to be inspected coated with a fluorescent adhesive containing a fluorescent agent with ultraviolet rays, and a detection unit for detecting fluorescence emitted from the fluorescent adhesive. It is characterized by that.

According to the present invention, a fluorescent agent is added to a commonly used adhesive so that the application state such as the application position and the application amount of the adhesive can be easily inspected. The fluorescent agent may be any as long as it emits fluorescence upon irradiation with ultraviolet rays, for example,
Select from commercially available Rhodamine, Auramine, etc. in consideration of color tone, toxicity, etc. according to the purpose. On the other hand, the adhesive
It may be selected according to the application, but it is preferably close to transparent so that it easily fluoresces when irradiated with ultraviolet rays by adding a fluorescent agent. For example, UV curable adhesives have toughness,
A urethane acrylate adhesive that is a type of this UV-curable adhesive because it has high abrasion resistance and flexibility and is widely used not only as an adhesive but also as a coating agent and sealing agent in electronic and electrical applications. Is useful as the main component of the fluorescent adhesive of the present invention.

The blending ratio of the fluorescent agent is preferably 0.1 to 1% by weight based on the adhesive to be prepared.
If the amount of the fluorescent agent added is less than 0.1% by weight, the emitted fluorescence becomes weak and detection becomes difficult. On the contrary, if it exceeds 1% by weight, curing failure may occur. Then, regarding the inspection method, when the inspection object coated with the fluorescent adhesive as described above is irradiated with ultraviolet rays (for example, light having a wavelength of about 365 nm is irradiated by a so-called black light or the like), the fluorescent agent is added. Only the portion of the adhesive becomes visible, and it becomes easy to visually check the application state such as the application position and the application amount of the adhesive.

Therefore, the fluorescence emitted from the above-mentioned fluorescent adhesive can be visually confirmed or captured by a camera and subjected to image processing to judge whether the adhesive application state is acceptable or not. For example, the inspection can be fully automated without relying on human eyes. It should be noted that the addition of the fluorescent agent is not limited to the adhesive, but the addition of the fluorescent agent to oil, grease or the like allows the state of coating and sealing to be easily inspected.

[0012]

When a fluorescent agent is added to an ordinary adhesive, it becomes a fluorescent adhesive which emits fluorescence upon irradiation with ultraviolet rays. Therefore, when the object to be inspected is irradiated with ultraviolet rays when inspecting the state of application of the adhesive, the applied position and the applied amount of the adhesive are easily visible due to the fluorescence emitted. Further, the inspection of the adhesive application state can be automated by the camera and the image processing device that capture the fluorescence emitted as described above.

[0013]

EXAMPLES The present invention will be described below based on concrete experimental results.

First, a fluorescent adhesive was prepared as follows. Urethane acrylate-based UV-curable adhesive (Kemitec, trade name ChemiSeal 4x174) 9
9.5 wt% was mixed with 0.5 wt% of a commercially available fluorescent agent Rhodamine B sufficiently ground in a mortar or agate.
Stirring was well performed using a stirrer or a triple roll so that Rhodamine B was uniformly dispersed.

Next, a method of inspecting the adhesive application state will be described. FIG. 1 shows an example of an inspection system for inspecting the application state of an adhesive. Fluorescent adhesive 1
The adherend or platen 2 coated with is placed on the conveyor 7 and is successively subjected to the inspection process. The inspection device is
The black light 3 for irradiating the platen 2 on the conveyor 7 with ultraviolet rays and the VTR camera 4 for sending an image to the image processing device 5 are the main components, and these are the fluorescent adhesive 1 It is installed so as to be located above the applied platen 2. The image captured by the VTR camera 4 can be confirmed on the monitor 6 connected to the image processing device 5.

In the above inspection system, since the illuminance of the fluorescent light emitted from the fluorescent adhesive 1 is low and the ultraviolet light emitted from the black light 3 is harmful,
A black light 3 that radiates ultraviolet rays, a platen 2 to which a fluorescent adhesive 1 that is an object to be inspected is attached, and V that captures fluorescence
It is preferable to cover the TR camera 4 with a dark box 8.

The platen 2 is conveyed to the inspection step by the conveyor 7 and is irradiated with ultraviolet rays from the black light 3. At this time, if the fluorescent adhesive 1 is not in the correct position on the platen 2, it should emit fluorescence. Fluorescence will be emitted from a position that is not. Then, the VTR camera 4 captures this fluorescence and sends an image to the image processing device 5, and determines that the application position of the adhesive is abnormal. Further, since the processed image is displayed on the monitor 6, it is possible to accurately confirm the abnormality in the application position of the adhesive.

In this system, the fluorescent adhesive 1
The fluorescence emitted by is captured by the VTR camera 4, the image is processed by the image processing device 5, and the pass / fail judgment of the adhesive application state is made. Must somehow eliminate the platen 2, which is a rejected product. Therefore, when it is determined that the test has failed, for example, (1) the monitor 6 indicates that the test has failed. (2) Stop the conveyor 7 so that it does not flow to the subsequent process. (3) Stop the platen 2 using the stopper. (4) Sound an alarm indicating failure. (5) Turn on a lamp indicating that the test has failed. (6) Mark the platen 2 for failure. The rejected product is removed by the method described above.

Further, in FIG. 1, an image of the platen 2 coated with the fluorescent adhesive 1 is captured from the Z-axis direction. However, depending on the position and shape of the fluorescent adhesive 1,
Images from the X-axis or Y-axis may be captured. Further, the volume of the fluorescent adhesive 1 can be measured by combining these images.

In this embodiment, an automatic inspection system using an image processing apparatus has been shown. However, even in the visual inspection of the adhesive application state, the use of the fluorescent adhesive and the black light for irradiating the ultraviolet rays makes it possible to detect the adhesive. The application position and application amount can be easily confirmed, and the inspection efficiency is improved.

[0021]

As is apparent from the above description, when the fluorescent adhesive of the present invention is used, the object to be inspected that is difficult to visually identify, for example, the object to be adhered and the adhesive having a similar color Also, by irradiating ultraviolet rays, it becomes possible to easily confirm the application position and the application amount of the adhesive.

In addition, a series of systems is introduced in which the fluorescence emitted by the fluorescent adhesive on the object to be inspected is captured by a camera, image processing is performed, and it is determined whether the application position or amount of the adhesive is appropriate. As a result, the inspection process of the adhesive application state can be automated. Furthermore, when defects such as foreign matter adhesion are found in other inspection steps, if the fluorescent adhesive of the present invention is used, whether or not the foreign matter is an adhesive can be determined by a simple operation of irradiation with ultraviolet rays. There is also an advantage that it can be determined.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing an example of an adhesive application state inspection system.

[Explanation of symbols]

 1 ... Fluorescent adhesive 2 ... Substrate (platen) 3 ... Black light 4 ... Camera 5 ... Image processing device 6 ... Monitor 7 ... Conveyor

Claims (5)

[Claims] 1. A fluorescent adhesive containing a fluorescent agent. 2. The fluorescent adhesive according to claim 1, wherein the content of the fluorescent agent is 0.1 to 1 part by weight. 3. The fluorescent adhesive according to claim 1, wherein the main component is a urethane acrylate-based ultraviolet curable adhesive. 4. A method for inspecting the state of application of an adhesive, which comprises irradiating an object to be inspected coated with a fluorescent adhesive containing a fluorescent agent with ultraviolet rays. 5. A light source for irradiating an object to be inspected coated with a fluorescent adhesive containing a fluorescent agent with ultraviolet light, and a detector for detecting fluorescence emitted from the fluorescent adhesive. Adhesive coating condition inspection device.