JP2701293B2 - Laser marking material and marking method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a material suitable for marking using laser light and a marking method using this material, for example, electric / electronic parts, cases and products The present invention relates to a material and a method effective for displaying a mark on the surface of an article, such as an article.

[Problems to be solved by conventional technology and invention]

Conventionally, the marking of characters and symbols on the surface of articles such as semiconductors, resistors, capacitors, relays, switches, and other electric and electronic parts, various electric products, etc., uses thermosetting or ultraviolet-curing marking ink. It is done by printing. This method has problems such as difficulty in marking fine parts and complicated maintenance and management of print quality.
In recent years, a laser marking method has been performed in which a surface of an article such as a part is directly irradiated with laser light and a part of the surface is eliminated by evaporation or thermal decomposition. However, there are various materials of the article to be marked, and there is a disadvantage that clear marking cannot be performed depending on the material.

[Means for solving the problem]

The present inventors have conducted intensive studies to eliminate the above-mentioned disadvantages of the marking, and as a result, when the surface of an article made of a material containing a boric acid-containing inorganic material is irradiated with laser light, the irradiated part and the unirradiated part have a clear appearance. The present inventors have found that high contrast and clear marking can be obtained, and have completed the present invention.

That is, the present invention is characterized in that a laser marking material characterized by being made of a transparent resin material containing a boric acid-containing inorganic material, and that a mark is displayed by irradiating a laser beam on the surface of an article made of this material. To provide a marking method.

As the borate-containing inorganic substance used in the present invention, zinc borate,
Aluminum borate, manganese borate, magnesium borate, lithium borate, copper borate, cobalt borate, sodium borate, calcium borate, potassium borate,
Examples include barium borate, boric acid-based glass, potassium metaborate, sodium metaborate, barium metaborate, lithium metaborate, lead metaborate, and calcium metaborate. Further, these inorganic substances may contain water of crystallization.

The marking material of the present invention may be any transparent resin material containing a boric acid-containing inorganic material, such as a molding material or a coating material containing a boric acid-containing inorganic material. Anhydrous zinc borate, anhydrous aluminum borate, anhydrous lithium borate, and anhydrous calcium borate are preferred in that a good coating material can be obtained, and anhydrous lithium borate and anhydrous calcium borate are particularly preferred in terms of excellent transparency and coloring. Is preferred.

The content of the inorganic substance containing boric acid is the content of the inorganic substance containing boric acid in the article made of the laser marking material of the present invention, for example, the molded article obtained by molding the molding material, the coating material applied and cured. 5 to 80% by weight, preferably 15 to 60%
If the content is less than 5% by weight, a clear contrast cannot be obtained, and if the content exceeds 80% by weight, the physical properties of a molded article or a coated article will be significantly impaired. Not preferred.

As the transparent resin material used for the molding material, the type thereof is not particularly limited, but a thermoplastic resin capable of extrusion molding, transfer molding, injection molding, blow molding, cast molding, press molding, etc., for example, Polyolefin resin, vinyl chloride resin, polystyrene resin, acrylic resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polycarbonate resin, polyacetal resin, polyphenylene sulfide resin, polyamide resin, polyimide resin, and copolymers thereof,
Thermosetting resins, such as epoxy resins, phenolic resins,
Examples include urea resin, melamine resin, polyester resin, acrylic resin, diallyl phthalate resin, urethane resin, aniline resin, furan resin, polyimide resin, silicone resin, and copolymers thereof.

The type of the transparent resin material used for the coating material is not particularly limited, but brush coating, spray coating, dip coating, roll coating, electrostatic coating, powder coating, transfer, printing, etc. are possible. The same thermosetting resin as above,
And an ultraviolet curable resin, an electron beam curable resin, and the like.

In addition, additives and the like can be added to the resin used for the molding material and the coating material, if necessary. Examples of the additives include a curing agent, a crosslinking agent, a photoinitiator, a dispersant, and a fluidity regulator. Any of the materials used in ordinary resin molding or resin coating, such as a mold release agent, a filler, a flame release agent, a lubricant, a stabilizer, an antioxidant, and a colorant, may be used.

In the present invention, a clear marking can be obtained by irradiating a laser beam having an appropriate intensity to a surface of a resin molded product or a resin coated product made of the material of the present invention containing a boric acid-containing inorganic material through a mask. .

As the laser used in the marking method of the present invention,
Among them, a carbon dioxide laser is preferable.

〔Example〕

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. All parts in the examples are parts by weight.

Example 1 Bisphenol F type epoxy resin 36 parts [Epiclon 830, epoxy equivalent 180, manufactured by Dainippon Ink & Chemicals, Inc.] Acid anhydride curing agent 31 parts [Epiclon B-570, acid anhydride equivalent 166, manufactured by Dojo Co.] Curing accelerator (benzyldimethylamine) 0.7 parts Zinc borate powder 28.8 parts Coloring agent (cobalt blue) 3.5 parts Epoxy resin composition of the above composition is uniformly mixed with three rolls to obtain a molding material. 5m between glass plates
After casting to a thickness of m, the mixture was cured at 80 ° C. for 5 hours and at 160 ° C. for 5 hours to obtain a blue transparent test piece. Next, the test piece was irradiated with laser light for about 1 μsec through a predetermined mask using a TEA carbon dioxide laser. A clear white marking was obtained on the surface of the test piece.

Comparative Example 1 A blue test piece was prepared in the same manner as in Example 1 except that the addition of the zinc borate powder was omitted, and the surface of the test piece was irradiated with laser light in the same manner. However, unlike Example 1, clear marking was not obtained.

Example 2 PEG600 diacrylate 64.5 parts [NK ester A-600 manufactured by Shin-Nakamura Chemical Co., Ltd.] Photoinitiator (α-hydroxyisobutylphenone) 3.2 parts Aluminum borate 30.3 parts Colorant (cobalt blue) 2 parts The composition was uniformly mixed with a lab mixer to obtain a coating material, which was placed on a glass plate with a bar coater at 70μ.
After coating to a thickness of m, the composition was irradiated with ultraviolet light from a high-pressure mercury lamp and cured to obtain a blue transparent test piece. Next, when laser light irradiation was performed in the same manner as in Example 1, transparent white marking was obtained.

Example 3 80 parts of PEG600 diacrylate 4 parts Photoinitiator (α-hydroxyisobutylphenone) 4 parts Cobalt borate (cobalt purple nova) 16 parts The above composition was uniformly mixed with a laboratory mixer to obtain a coating material. 70 μm on a glass plate with a bar coater
After thick coating, it was cured by irradiating ultraviolet rays with a high pressure mercury lamp to obtain a purple transparent test piece. Subsequently, when laser light was irradiated in the same manner as in Example 1, white marking was obtained although it was slightly unclear.

Comparative Example 2 93 parts of PEG600 diacrylate 3 parts Photoinitiator (α-hydroxyisobutylphenone) 3 parts Cobalt borate (cobalt purple nova) 4 parts A coating material was prepared in the same manner as in Example 3 except that the composition having the above composition was used. After coating, the composition was cured by ultraviolet rays to obtain a purple test piece. Next, when laser light was irradiated in the same manner as in Example 1, no clear marking was obtained.

Example 4 Polyethylene resin (Sumikacene G808 ^... , MI = 200) 56 parts [Sumikasen G808 manufactured by Sumitomo Chemical Co., Ltd., MI 200 g / mi
n] Magnesium anhydrous borate 42 parts Coloring material (dark blue) 1.4 parts Dispersant (zinc stearate) 0.6 parts The composition having the above composition is sufficiently kneaded at 140 ° C. using a laboratory plastomill manufactured by Toyo Seiki Co., Ltd. to form a molding material. This was formed into a sheet having a thickness of 1 mm using a heating press machine, and cooled to obtain a blue transparent test piece. Next, when a laser beam was irradiated in the same manner as in Example 1, clear white marking was obtained.

Comparative Example 3 A blue test piece was obtained in the same manner as in Example 4 except that the addition of anhydrous magnesium borate was omitted. Next, when laser light was irradiated in the same manner as in Example 1, no clear marking was obtained.

Examples 5 to 9 PEG 600 diacrylate 64.5 parts Photoinitiator (α-hydroxyisobutylphenone) 3.2 parts Boric acid-containing inorganic substance shown in Table 1 32.3 parts The composition having the above composition was uniformly mixed with a laboratory mixer to prepare a coating material. Obtained and placed on a glass plate with a bar coater 70 μm
After thick coating, the coating is cured by irradiating ultraviolet rays with a high-pressure mercury lamp to obtain a transparent to cloudy test piece. Next, a white marking was obtained by irradiating a laser beam in the same manner as in Example 1, and the coloring and transparency were evaluated according to the following criteria.
The results are shown in Table 1.

Coloring property of the marking part irradiated with laser light ◎: Particularly good ○: Good Transparency of the non-marking part not irradiated with laser light ◎: Particularly good ○: Good △: Slightly cloudy ×: Transparency is recognized but cloudy strong [Effects of the Invention] Irradiation of the surface of an article made of the material for laser marking of the present invention with laser light has an effect that clear marking can be easily performed.

Continuation of the front page (56) References JP-A-62-248682 (JP, A) JP-A-1-215589 (JP, A) JP-A-62-152791 (JP, A) JP-A-49-113810 (JP) , A)

Claims (6)

(57) [Claims] 1. A laser marking material comprising a transparent resin material containing a boric acid-containing inorganic substance. 2. The laser marking material according to claim 1, which is a coating material. 3. The laser marking according to claim 2, wherein the boric acid-containing inorganic substance is at least one kind of anhydrous boric acid-containing inorganic substance selected from anhydrous zinc borate, anhydrous aluminum borate, anhydrous lithium borate and anhydrous calcium borate. Materials. 4. A marking method comprising irradiating a surface of an article made of a transparent resin material containing a boric acid-containing inorganic substance with a laser beam to display a mark. 5. The marking method according to claim 4, wherein the transparent resin material containing a boric acid-containing inorganic substance is a coating material. 6. The marking method according to claim 5, wherein said boric acid-containing inorganic substance is at least one kind of anhydrous boric acid-containing inorganic substance selected from anhydrous zinc borate, anhydrous aluminum borate, anhydrous lithium borate and anhydrous calcium borate. .