JPH0594904A - Marking method for electric part - Google Patents

Abstract

PURPOSE:To visually discriminate a marking easily irrespective of the color of the outside surface of an electronic part by a method wherein the background of the making is put in the original color of a film, not in the color of the outside surface of the electronic part. CONSTITUTION:A film 5, which changes color by the irradiation of a laser beam, is formed on the outer surface of an electronic part 1 in advance, and then a laser beam P is made to cast on the surface of the film 5. This is the method for marking of an electronic part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of marking a serial number or the like on the outer surface of an electronic component.

[0002]

2. Description of the Related Art Conventionally, in a chip type electronic component, marking has been performed by intaglio transfer printing. However, intaglio transfer printing, it is difficult to mark ultra-small chip-type electronic components. Also, when marking a large number of characters on a large chip-type electronic component, there is a limit to the size of the characters and the thickness of the line, and it is difficult to mark a large number of characters in a limited area. ..
Therefore, in recent years, as a method for solving the above problems, a marking method using a laser beam has been proposed and implemented. In this method, marking is performed by irradiating the outer surface of the electronic component with laser light and baking the outer surface of the electronic component with the laser light. In the marking method using laser light, very small characters and thin lines can be drawn, so that marking of a desired size can be surely performed even on a microminiature chip-type electronic component.

[0003]

However, while the color of the outer surface of the chip type electronic component is various, the color of the character formed by the marking method using laser light is black. Therefore, depending on the color of the outer surface of the electronic component,
For example, in the case of a relatively dark dark color such as brown, it tends to be difficult to visually distinguish the marking. As a result, it was impossible to visually inspect the chip-type electronic component mounted on the completed substrate. Further, since it was not possible to visually identify the chip-type electronic components, when different types of chip-type electronic components are mixed in a large number of chip-type electronic components, the different types of chip-type electronic components are visually identified and separated. I couldn't. Therefore, it is necessary to inspect a large number of chip-type electronic components, which are considered to be mixed with different types of chip-type electronic components, by measuring the characteristics and the like again, or even discard them.

An object of the present invention is to make it possible to easily visually discriminate the markings regardless of the color of the outer surface of the electronic component and to apply the electronic component to a microminiature chip type electronic component. It is to provide a marking method for parts.

[0005]

SUMMARY OF THE INVENTION The present invention is a method for marking an outer surface of an electronic component by irradiating the outer surface with a laser beam, in which a film that changes color by the irradiation of the laser beam is previously formed on the outer surface of the electronic component. The method for marking electronic parts is characterized by irradiating the surface of the film with a laser beam. The material for forming the film that changes color by irradiation with laser light is not particularly limited, and any appropriate material that changes color by irradiation with laser light can be used. An example is a white film formed by applying a titanic acid-containing paste. In this case, titanic acid is reduced by irradiation with laser light, and the marking portion is blackened.

[0006]

[Function] Prior to the irradiation of laser light, a film that changes color due to irradiation of laser light is formed on the outer surface of the electronic component. It Since the background color of the marking is not the color of the outer surface of the electronic component but the original color of the film, the marking can be easily visually identified regardless of the color of the outer surface of the electronic component. ..

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the electronic component marking method of the present embodiment, first, as shown in FIG. 2, the chip type electronic component 1 is prepared. In the chip-type electronic component 1, internal electrodes (not shown) are formed inside an electronic component element body 2 made of ceramics, and a pair of external electrodes 3 and 4 electrically connected to the internal electrodes are electronic. It is formed on both end faces of the component body 2. In the marking method of the present embodiment, the white film 5 is formed by applying a white titanic acid-containing paste on the upper surface of the electronic component element body 2 and drying it.

Next, as shown in FIG. 1, laser light P is irradiated from above the white film 5 to form markings 6 (characters indicated by A and B). The marking 6 is formed by irradiating the laser beam P to change the color of the irradiated portion of the white film 5 and turn it black. Therefore, according to the marking method of the present embodiment, the black marking 6 is formed in the white background, so that the marking 6 can be easily discriminated visually. Moreover,
Since the main background color of the marking 6 is not the color of the electronic component element body 2 but the color of the film 5, that is, white, regardless of the color of the electronic component element body 2, the marking 6 can be visually and easily confirmed. Can be determined.

In the above embodiment, the film 5 for forming the background of the marking was formed by applying and drying the titanic acid-containing paste, but other resin or ink other than the titanic acid-containing paste is used. May be used to form the film 5. In short, the film 5 can be formed by using any resin or ink that changes color due to alteration when irradiated with laser light. Examples of such a resin or ink include a copper oxalate-containing resin and the like, and an appropriate pigment or dye for forming a background color is added to the synthetic resin or ink as needed. However, it is preferable to use a material such as the titanic acid-containing paste that changes its color from the original color to a color that can be easily visually discerned. Further, it is preferable to use one having a certain degree of solvent resistance.

Further, the planar shape of the region where the film 5 is formed can be appropriately changed according to the desired marking, and for example, a rectangular film 5 may be formed as shown in FIG. Any laser device such as a CO ₂ excimer laser can be used as the laser beam for marking, and as long as it can change the color of the film 5, the laser device with relatively low output is used to perform the marking. It can be carried out.

[0011]

According to the present invention, a film that changes color by irradiation with laser light is formed in advance on the surface of an electronic component, and marking is performed by irradiating the film with laser light. Regardless of, the background color of the marking will always be the original color of the film. Therefore, it is possible to form a marking that can be easily discriminated visually regardless of the color of the outer surface of the electronic component. Moreover, because the marking method uses laser light, marking can be performed on ultra-small chip-type electronic components, and even when large numbers of characters are marked on large chip-type electronic components, the size of the characters The marking can be accurately formed regardless of the thickness of the sheath line.

Therefore, in the electronic component marked by the method of the present invention, the marking can be easily discriminated by the naked eye, so that the electronic component can be surely inspected visually by visual inspection with the electronic component mounted on the finished substrate. Even when different kinds of electronic parts are mixed, it is possible to easily separate the different kinds of electronic parts visually.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining a process of marking by irradiating a laser beam in an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a film that changes color by irradiation with laser light is formed on the outer surface of the electronic component.

FIG. 3 is a perspective view showing another example of the planar shape of a film that changes color when irradiated with laser light.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic component 2 ... Electronic component base body 5 ... Film that changes color by irradiation of laser light 6 ... Marking P ... Laser light

Claims (1)

[Claims] 1. A method for marking by irradiating a laser beam on an outer surface of an electronic component, wherein a film that changes color by irradiating a laser beam is previously formed on the outer surface of the electronic component, and then the film is formed. A method for marking electronic parts, characterized by irradiating a surface with laser light.