JPS5867496A - Marking method - Google Patents

Abstract

PURPOSE:To obtain a clear mark with lesser lesers energy in a short time by a method in which a marking layer is provided near the surface of an object to be printed, molded of a resin, and the marking layer is etched by means of lasers. CONSTITUTION:In the manufacture of a resin molding, e.g., electronic parts, etc., a resin component 21 is mixed with at least 30wt% or more a white fine powder 22, e.g., silicone oxide or alumina, in such a way that a white fine powder layer 12 containing the white fine powder 22 is formed in the area within maximumly 2mum from the surface 24 of the resin layer 11 composed of the resin component 21. Then, lasers is irradiated onto the resin surface 24 to etch the white fine powder layer 12 present within 5mum from the resin surface. By this, a clear mark with a contrast distictive to the resin layer 11 and the black fine powder 23 surrounding the etched part can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a marking method for marking objects such as parts or devices molded from resin.

Conventionally, the manufacturer's name is used for electronic components such as resistors and capacitors, or semiconductor devices such as transistors, diodes, and integrated circuits.

When marking the variety name, domestic product code, etc.,
A method of directly or indirectly printing using white or silver marking ink, that is, a mechanical transfer marking method has been adopted.

However, with this mechanical transfer marking method, ink smearing occurs, the drying process is indispensable,
Various problems such as difficulty in achieving the proper concentration of ink remain unresolved. Also, the price occupied by the marking process compared to other processes where rationalization is progressing.

The current situation is that the proportion of time is increasing.

On the other hand, with the recent progress in the application of laser beams, a laser marking method has been put into practical use instead of the above-mentioned printing method in order to meet the current melting point requirements.

Conventionally, there are two methods for this laser marking method.

A technique was used to increase the sharpness of the resin by etching the resin with a laser beam as deeply as possible, creating a step deeper than the overall surface.

This is due to the fact that the white differential 2 components such as silicon oxide or alumina contained in the molded resin layer 1 as shown in FIG. 141 are small and are uniformly dispersed in the resin layer 1. For this reason, conventionally, the etching depth h of the resin layer l
has no choice but to increase the depth (usually 10~20P deep),
This method requires a relatively large amount of radar energy and has a slow marking speed. 8% 51% 1st factor 1 is black fine powder such as carbon or manganese oxide for the purpose of black coloring.

This invention was made in view of the above circumstances, and its objectives are to reduce the laser energy required for laser etching, increase the marking speed, i.e., increase the throughput per unit time, and provide clear marks. The object of the present invention is to provide a marking method with improved accuracy.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

The resin used is a synthetic Ij14 containing white fine powder such as silicon oxide or alumina of at least 30 or more.
For example, epoxy, silicone, or acrylic resins are used.Today's transistors, integrated circuits, etc. are mainly made of epoxy or silicone resins. A common method is to incorporate black fine powder such as carbon or manganese oxide for the purpose of black coloring, and package it by transfer molding or casting technology.

FIG. 2 shows the resin used as the printing material molded by such a method. In the same figure, 11 is a resin 114 mainly consisting of a resin component 21, 121 is a white fine powder layer mainly consisting of white fine powder 22 and serving as a mark layer;
3 is a dispersion layer in which a resin component 21 and a white fine powder 22 are dispersed approximately evenly, 23 is a black fine powder, and 24 is a resin surface corresponding to a portion that was left behind by a mold during molding. Na χ.

The white fine powder layer 12 is at least 30% by weight in #fat.
This is because it contains the above white fine powder 21f.

It exists within a maximum of 5 μm from the resin surface 24.

In such a configuration, when the resin surface 24 is irradiated with a laser beam whose energy is adjusted to be smaller than before, the resin surface 24 is etched as shown in the third factor, and the resin surface 24 is
It reaches the white fine powder layer lJ that exists at a slightly deeper place (within 5 μm) than the white powder layer lJ. At this time, since the white fine powder layer l-2 exists within a maximum of 5 μm from the resin layer 1i1124, the white fine powder layer 11 can be etched in a short time with small laser energy.

Also, the purpose is to etch the white fine powder layer J-7.

Therefore, the resin layer 11 around the etched portion (mark)
It also forms a contrast with the black fine powder 23,
The mark becomes clear. The fourth factor is a plan view showing the state of etching.

In Example 8 above, the mark layer is a white fine powder layer 1'IC made of silicon oxide or alumina, but is not limited to this. It may also be a coloring agent or a flavoring agent.

As described above, according to this invention, +f, tree jl (:.

Contain at least 30 layers of powder of a color different from that of the resin, and form a mark layer containing this fine powder as the main component.
The mark layer is formed within 5 μm in depth from the surface of the fat and etched with a laser beam, which reduces the amount of laser energy required and increases the marking speed, increasing throughput per unit time. In addition, if the mark layer and the resin surface are painted in a contrasting color, the sharpness of the mark will improve.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a printing material showing the state of etching by a conventional laser beam, FIG. !
The sectional view shown and the fourth factor are also plan views. dispersed layer, 21...resin component, 22...white fine powder, z3
...Black fine powder.

Claims (1)

[Claims] (1) A method of marking a printing material molded from resin by irradiating it with a laser beam. A mark layer is provided within a depth of 5 μm from the surface of the resin,
A marking method characterized in that this mark layer "4f is etched by the laser beam. (No. The marking method according to claim 1, wherein at least 30J1:FITS is contained in the marking method.