JPH08187943A - Resin composition for laser marking and electronic parts using the composition - Google Patents

Abstract

PURPOSE: To provide a resin compsn. for laser marking enabling durable and sharp display and electronic parts using the same. CONSTITUTION: A resin compsn. contains a metal compd. discolored by the irradiation with laser beam, an antirust agent and a resin. The surface of the mental compd. is covered with the antirust agent. Further, the resin has a property cured by either one of ultraviolet rays, visible light and electron beam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for laser marking, which is suitable for marking by irradiation with laser light having a wavelength in the far infrared region, and an electronic component using the resin composition.

[0002]

2. Description of the Related Art As a method of marking a product name, a lot number, etc. on a package of electronic parts, there are a method such as printing with ink and a method of laser marking.

Of these, the laser marking method is advantageous in that it is not affected by the surface condition of the product by non-contact processing, the line can be speeded up and automated, and the marking can be miniaturized. Recently, it is widely used industrially.

Laser marking methods include (1) a method of utilizing surface shape change due to irradiation of laser light and (2) a method of utilizing surface discoloration.

[0005]

[Problems to be Solved by the Invention] However, (1)
The method utilizing the change in the shape of the surface has a problem that a clear marking cannot be obtained because the contrast between the laser light irradiation portion and the non-irradiation portion is weak.

On the other hand, the method (2) utilizing the discoloration of the surface requires the use of a material which discolors by the energy of laser light, but the number of materials of this kind is limited. In addition, a material that is easily discolored by laser light is generally chemically unstable, and tends to be easily discolored by heat in a processing process or a reaction with another material. Further, it is important that a portion that has been discolored by laser light is difficult to be discolored or discolored in the environment such as high temperature and high humidity thereafter, but such a material is difficult to obtain.

In order to solve such a problem, the inventors of the present invention have increased the blackness of the color-developed portion by reducing the particle size of the material that changes color with laser light (Japanese Patent Laid-Open No. Hei 10-1999). 6-55853). And
As a method for pulverizing the color-change material, a wet method such as a ball mill method or a sand mill method, or a dry method such as a jet mill has been used.

By the way, a resin composition containing a metal compound is discolored (blackened) by being irradiated with a laser beam, because the resin material is carbonized by the energy of the laser beam and the metal compound is reduced at that time. This is because. The reduced metal compound becomes fine particles of a simple metal, and the fine particle metal shows black. This is the color change mechanism of laser marking.

For this reason, the metal of the discolored portion is easily oxidized by an environmental test such as being left in a high humidity and is changed to an oxide to lower the blackness. Even if the discoloration agent is further finely divided to increase the initial blackness, It was not a fundamental solution for improving moisture resistance.

Therefore, an object of the present invention is to provide a resin composition for laser marking which enables durable and clear display by laser marking, and an electronic component using the same.

[0011]

In order to achieve the above object, the resin composition for laser marking of the present invention contains a metal compound that changes color by irradiation with laser light, a rust preventive agent, and a resin. Is characterized by.

Further, the surface of the metal compound is covered with a rust preventive agent.

Further, the resin is characterized by being cured by any one of ultraviolet rays, visible rays and electron rays.

The electronic component of the present invention is coated with an insulating material containing a metal compound, a rust preventive agent, and a resin,
Moreover, the coating is marked by the discoloration of the metal compound caused by laser light irradiation.

The surface of the metal compound is covered with a rust preventive agent.

Furthermore, the electronic component of the present invention is coated with an insulating material containing a metal compound and a resin, and is marked on the coating by discoloration of the metal compound due to laser light irradiation, and the marking surface. Is covered with a rust preventive agent.

[0017]

The function of the resin composition for laser marking of the present invention is
It contains a metal compound that changes color when irradiated with laser light, a rust preventive agent, and a resin. By irradiating the resin composition with a laser beam, the metal compound is reduced to become a metal, and a marking that is discolored black is obtained. Then, this metal is oxidized by moisture in the air and the black color is reduced, adding a rust preventive agent to the resin in advance, treating the metal compound with the rust preventive agent beforehand, or laser light It can be prevented by irradiating to discolor the metal compound and then treating with a rust preventive.

[0018]

EXAMPLES Examples of the present invention will be described below. (Example 1) First, a resin composition for laser marking in the form of a coating material was obtained as follows. That is, 100 parts by weight of a bisphenol A-based epoxy acrylate resin (Showa Polymer Co., Ltd., Lipoxy SP-1509) as a resin, a reactive diluent (Kyoeisha Chemical Co., Ltd., THF-A).
60 parts by weight, 3 parts by weight of a photoinitiator (Irgacure 184 manufactured by Nippon Ciba-Gigi Co., Ltd.), and 30 parts by weight of basic lead phosphite (average particle size: 0.54 μm) as a metal compound,
3 parts by weight of sorbitan monooleate as a rust preventive was well mixed to obtain a resin composition for laser marking in the form of a coating material, which was an ultraviolet curing type and was in the form of a coating material.

Next, a thick film resistor circuit was formed on an alumina substrate in advance, and the above resin composition was applied to the alumina substrate main body portion of the resistor circuit component in which lead terminals were attached to the terminal electrode portions thereof. And the dominant wavelength is 365 nm,
Light quantity is irradiated with ultraviolet rays ^of 1000 mJ / cm ^2, to cure the resin composition of the paint form. Then, the cured surface was irradiated with TEA-CO ₂ laser light through a predetermined mask to make a clear black marking to complete the resistance circuit component.

Thereafter, the resistance circuit component is heated to a temperature of 85 ° C.
It was put into a high temperature and high humidity tank having a relative humidity of 85% and taken out every 250 hours, and the degree of color change of the marking was visually confirmed.

(Example 2) First, a resin composition for laser marking in the form of a coating material was obtained as follows. That is, 1 wt% of sorbitan monooleate as a rust preventive agent
After dipping basic lead phosphite (average particle size: 0.54 μm) as a metal compound in a toluene solution having a concentration,
It was thoroughly dried in a convection oven at 120 ° C. next,
30 parts by weight of basic lead phosphite whose surface is covered with a rust preventive agent, and a bisphenol A epoxy acrylate resin (Repoxy SP-1 manufactured by Showa High Polymer Co., Ltd.) as a resin composition.
509) 100 parts by weight, a reactive diluent (manufactured by Kyoeisha Chemical Co., Ltd., THF-A) 60 parts by weight, and a photoinitiator (manufactured by Japan Ciba-Gaigi Co., Ltd., Irgacure 184) 3 parts by weight are mixed well, An ultraviolet curable resin composition for laser marking in the form of a paint was obtained.

Next, this resin composition was applied to the main body of the alumina substrate of the resistance circuit component in the same manner as in Example 1 and irradiated with ultraviolet rays having a main wavelength of 365 nm and a light intensity of 1000 mJ / cm ² to cure the resin composition. It was Then, the cured surface was irradiated with TEA-CO ₂ laser light through a predetermined mask to make a clear black marking to complete the resistance circuit component.

Thereafter, the resistance circuit component is heated to a temperature of 85.degree.
It was put into a high temperature and high humidity tank having a relative humidity of 85% and taken out every 250 hours, and the degree of color change of the marking was visually confirmed.

(Example 3) First, a resin composition for laser marking in the form of a coating material was obtained as follows. That is, that is, a bisphenol A epoxy acrylate resin as a resin composition (manufactured by Showa Polymer Co., Ltd., Lipoxy S
P-1509) 100 parts by weight, a reactive diluent (manufactured by Kyoeisha Chemical Co., Ltd., THF-A) 60 parts by weight, a photoinitiator (manufactured by Nippon Ciba-Gaigi Co., Ltd., Irgacure 184) 3 parts by weight, and as a metal compound. Basic lead phosphite (average particle size:
0.54 μm) and 30 parts by weight were thoroughly mixed to obtain an ultraviolet-curable resin composition for laser marking in the form of a paint.

Then, this resin composition was applied to the main body of the alumina substrate of the resistance circuit component in the same manner as in Example 1 and irradiated with ultraviolet rays having a main wavelength of 365 nm and a light intensity of 1000 mJ / cm ² to cure the resin composition. It was Then, the cured surface was irradiated with TEA-CO ₂ laser light through a predetermined mask to make a clear black marking. After that, a 1% concentration toluene solution of sorbitan monooleate as a rust preventive was applied to this marking portion and dried sufficiently in a convection oven at 120 ° C. to complete a resistance circuit component.

Thereafter, the resistance circuit component is heated to a temperature of 85.degree.
It was put into a high temperature and high humidity tank having a relative humidity of 85% and taken out every 250 hours, and the degree of color change of the marking was visually confirmed.

(Conventional Example) First, a resin composition for laser marking in the form of a coating material was obtained as follows. That is,
Bisphenol A type epoxy acrylate resin as resin composition (Showa Polymer Co., Ltd., Lipoxy SP-150)
9) 100 parts by weight, reactive diluent (Kyoeisha Chemical Co., Ltd.)
Manufactured by THF-A), 3 parts by weight of photoinitiator (Irgacure 184, manufactured by Nippon Ciba-Geigy Co., Ltd.), and basic lead phosphite as a metal compound (average particle diameter: 0.54 μm).
m) 30 parts by weight were mixed well to obtain a resin composition for laser marking which was an ultraviolet curable type and was in the form of a paint.

Then, this resin composition was applied to the main body of the alumina substrate of the resistance circuit component in the same manner as in Example 1 and irradiated with ultraviolet rays having a main wavelength of 365 nm and a light intensity of 1000 mJ / cm ² to cure the resin composition. It was Then, the cured surface was irradiated with TEA-CO ₂ laser light through a predetermined mask to make a clear black marking to complete the resistance circuit component.

Thereafter, the resistance circuit component is heated to a temperature of 85.degree.
It was put into a high temperature and high humidity tank having a relative humidity of 85% and taken out every 250 hours, and the degree of color change of the marking was visually confirmed.

Table 1 shows the degree of color change of the markings of Examples 1 to 3 and the conventional example. In Table 1, ○
The mark shows that the black color of the marking was almost the same as it was before putting it in the high temperature and high humidity tank, the □ mark shows that the black color of the marking became a little thin, the △ mark shows that the black color of the marking became considerably thin, and the X mark shows the marking. Is so thin that it is almost invisible.

[0031]

[Table 1]

As shown in Table 1, according to the present invention, the rust preventive agent is added to the resin in advance, the metal compound is treated with the rust preventive agent in advance, or the metal compound is irradiated with laser light to remove the metal compound. In any case of treating with a rust preventive after discoloring, deterioration of the sharpness of marking after laser marking is suppressed.

The resin composition for laser marking of the present invention is used, for example, in the form of molding material or paint. The resin used is not limited to the above example.

That is, when used as a molding material, for example, polyethylene, vinyl chloride resin, polypropylene, styrene resin, ABS resin, polyvinyl alcohol, acrylic resin, acrylonitrile-styrene resin,
Vinylidene chloride resin, fluororesin, polycarbonate,
Thermoplastic resins such as polyamide, acetal resin, polyphenylene oxide, polybutylene terephthalate, polyethylene terephthalate and polyphenylene sulfide, and thermosetting resins such as epoxy resin, phenol resin, unsaturated polyester resin, urethane resin, silicone, diallyl phthalate resin, etc. Can be used.

The molding method is not particularly limited,
For example, extrusion molding, transfer molding, injection molding, blow molding, press molding, cast molding and the like can be adopted.

When used as a coating material, the resin may be, for example, (1) a room temperature evaporation dry type mainly composed of the above-mentioned thermoplastic resin, and (2) a bake hardening type (mainly composed of the above-mentioned thermosetting resin. 3) There are room temperature-curing types such as oil-modified mainly by air oxidation that are found in polymerized oils and alkyd resins, but UV curable resins mainly composed of acrylate and unsaturated polyester that can be cured for a short time and have high productivity. First of all, a resin that cures in a short time by high-energy rays such as visible rays and electron rays is excellent.

The coating method is not particularly limited,
For example, dipping coating, spray coating, brush coating,
Electrostatic coating, powder coating, printing, etc. can be adopted.

Further, the resin composition used as the above-mentioned molding material or paint may contain a plasticizer, if necessary.
A heat stabilizer, a filler, a colorant, a combustion inhibitor, a release agent, a solvent and the like can be added.

Further, in the above-mentioned embodiment, basic lead phosphite is used as the metal compound which is discolored by irradiation with laser light, but the present invention is not limited to this. That is, as the metal compound that turns black by irradiation with laser, for example, a lead compound such as basic lead carbonate, basic lead phosphite, and basic lead sulfate,
Nickel compounds such as nickel carbonate and nickel oxalate,
Copper compounds such as copper hydroxide, copper oxalate, and copper carbonate can be used. Of these, the lead compound has the highest degree of blackening and is excellent for laser marking. When these metal compounds are made into fine powder, blackening is further enhanced. Further, these metal compounds can be contained in an amount of 2 to 90 wt% with respect to the resin solid content. However, if the content of the metal compound is small, the laser colorability is deteriorated. On the other hand, when the content of the metal compound is large, the physical properties of the cured product are deteriorated. Therefore, the content of the metal compound is preferably 5 to 50 wt%.

Although sorbitan monooleate is used as the rust preventive in the above embodiments, the present invention is not limited to this. That is, as the rust preventive agent, any of an oil-soluble rust preventive agent, a water-soluble rust preventive agent, and a vaporizable rust preventive agent may be used, and a compound classified as a surfactant can be used. Specifically, (a) soap of carboxylic acid such as naphthenic acid and abietic acid and a metal or amine,
(B) polyhydric alcohol fatty acid ester including fatty acid partial ester such as sorbitan and pentaerythritol, (c) petroleum sulfonate (d) phosphoric acid ester,
(E) Amine derivatives such as alkanolamides, imidazolines and quinolines can be used.

The laser light used in the present invention has a wavelength in the far infrared region. To obtain the laser light, for example, a TEA-CO ₂ laser having a wavelength of 10.6 μm or a wavelength of 1 is used. A YAG laser of 0.06 μm or the like can be used. And as a marking method, a method of irradiating a laser beam through a mask or the like,
There is a method of performing marking by scanning laser light.

Further, in the above embodiment, the case of the resistance circuit component is explained, but the present invention is not limited to this. That is, capacitors, resistors, coils, transformers, filters, oscillators, connectors,
Similar effects can be obtained in general electronic components such as switches, printed wiring boards, sensors, LSIs, active components such as individual semiconductors, and liquid crystal elements.

[0043]

As is apparent from the above description, according to the resin composition for laser marking of the present invention, the marking portion that is discolored to black due to the reduction of the metal compound into metal by laser irradiation is oxidized with time. The black marking can be prevented from being thinned by the rust preventive contained in the resin composition. The antioxidative action is to coat the metal oxide, which changes color with laser light, with a rust preventive agent in advance, or to irradiate the laser light to change the color of the metal compound, and then to cover the surface with a rust preventive agent. The more effective it is, the better.

Therefore, according to the present invention, a resin composition for laser marking, which enables durable and clear display by laser marking, can be obtained.

By using this resin composition for laser marking as an exterior resin for electronic parts, electronic parts having a durable and clear display by laser marking can be obtained.

Furthermore, by using a resin that can be cured by high energy rays such as ultraviolet rays, visible rays and electron rays as the resin in the resin composition for laser marking, it becomes possible to cure for a short time and when applied to electronic parts. Productivity is improved.

Claims (6)

[Claims] 1. A resin composition for laser marking, which comprises a metal compound that changes color when irradiated with a laser beam, a rust preventive agent, and a resin. 2. The resin composition for laser marking according to claim 1, wherein the surface of the metal compound is covered with a rust preventive agent. 3. The resin composition for laser marking according to claim 1, wherein the resin is cured by any one of ultraviolet rays, visible rays and electron beams. 4. A metal compound, a rust preventive, and a resin are coated with an insulating material, and the metal compound is discolored by laser light irradiation to mark on the coating. Electronic components to do. 5. The electronic component according to claim 4, wherein the surface of the metal compound is covered with a rust preventive agent. 6. An insulating material containing a metal compound and a resin is coated, and the metal compound is discolored by laser light irradiation to mark the coating, and the marking surface is covered with a rust preventive agent. An electronic component characterized by being.