JP3282094B2 - Recording body for laser marking and laser marking method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marking method and a method for marking various kinds of display objects which need to be displayed or recorded on the surface of a package of a factory shipment or a label attached to the factory shipment. Related to the recording body for
Any pattern such as product name, lot number, manufacturing time, expiration date, barcode, etc. input on the display body for its identification can be easily and efficiently processed at high speed just before production, packaging, etc., during the line, and immediately after. carbon dioxide laser marking recording body capable marking and relates to a laser marking method.

[0002]

2. Description of the Related Art Generally, as a laser marking method,
The surface of the base material is irradiated or scanned with a laser beam of an arbitrary pattern, and the colored layer such as the base layer of the base material is destroyed by evaporation and scattering, and the difference in lightness and hue between the exposed base and the non-destructive part,
Or, a destructive method of obtaining visibility by utilizing the contrast obtained by irregular reflection of light due to the unevenness of the destruction part, containing a compound that decomposes or reacts with heat and develops a color different from the original color by heat There is a coloring type method in which a laser coloring layer is formed on a recording medium, and the recording medium is irradiated with a laser beam to obtain visibility.

[0003] For example, as a destructive laser marking method, a colored ink layer printed on a wrapping paper or a paper label is destroyed by laser light, and the whiteness of the exposed underlying paper and the colored ink of the non-destructive portion are compared. There is a method using lightness and hue difference, and this method has high visibility, is simple and effective. However, this method has a problem in that, at the time of high-speed marking, equipment for collecting evaporated and scattered substances is required, and costs for maintenance and the like are required.

[0004] As a color-forming type laser marking method, a heat-sensitive coloring ink and an OP varnish are printed on a label to form a heat-sensitive coloring layer and a protective layer. There is a method of obtaining visibility based on the brightness and hue difference of an irradiated portion, and this method is effective with extremely few evaporation and scattered matters.

[0005]

However, in these laser marking methods, since a laser beam having a relatively high energy density is used, the laser beam penetrates the coloring layer or the laser coloring layer and damages the support of the recording medium. May cause or damage packaged products. If the support is damaged, the strength of the recording medium will decrease, or laser-marked characters,
There is a problem that binding on a support such as a pattern becomes weak, and the markings fall off. In addition, when the packaged product is irradiated with the transmitted strong laser beam, there are problems such as printing on the product and damage to the product surface.

An object of the present invention is to provide, in view of the above circumstances, online, contactless, in carbon dioxide laser marking method has a feature that high-speed marking, laser color in the laser irradiation of low energy density raw
More energy efficient, faster or wider print surface
Carbon dioxide gas that can be used to mark the product and suppress damage to the support and packaged products during laser marking.
An object of the present invention is to provide a recording material for laser marking, particularly a display for laser marking.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that, in a recording medium having a laser coloring layer on a support, a titanium oxide-coated cloud is provided between the support and the laser coloring layer.
When using a recording medium on which a shielding layer containing a mother or tetrafluorosilicic mica is formed, the carbonic acid transmitted during laser marking is used.
Can be the energy of the gas laser beam significantly lower by laser shielding layer, it found that to suppress the damage of the support or the packaged product, and have completed the present invention.

That is, the present invention is to solve the above-mentioned problems.
To, have a shielding layer containing a laser-screening agent on the support
Further , in a recording medium having a laser coloring layer on the shielding layer , the laser shielding agent may be titanium oxide-coated mica or
Provides carbon dioxide laser <br/> The marking recording medium, which is a fluorine tetrasilicon mica.

Further, the present invention has been made to solve the above problems.
To, have a shielding layer containing a laser-screening agent on the support
And a carbon dioxide for displaying or recording characters and / or graphics on a recording medium having a laser coloring layer on the shielding layer.
Irradiating the gas laser beam, the laser marking method of performing marking laser coloring layer discolored by heat,
Before SL laser blocking agent is titanium oxide-coated mica or fluorine tetrasilicic
Hisage the laser marking method which is characterized in that it is a mica
Offer .

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Typical and best modes of the embodiment of the present invention are specifically shown in the following examples. Will be described in detail.

As the laser shielding agent used in the present invention, acid
Titanium fluoride coated mica or tetrasilicon fluoride mica can be used. The laser shielding agent itself is dispersed in the form of particles in the support or a layer on the support, or is present in a state of being dissolved in a resin. When present in the form of particles, the average particle size is
Usually, it is 50 μm or less, particularly preferably 0.1 to 15 μm. In addition, these laser shielding agents may be surface-treated in advance with a titanium coupling agent, a silane coupling agent, a metal soap, a surfactant, a resin, or the like, in order to enhance uniformity when dispersed in the form of particles. .

[0019]

[0020]

[0021]

[0022]

[0023]

The laser shielding agent may be used alone or in combination of two or more. The support of the present invention is not particularly limited, and may be selected from durability and design properties required according to the intended use, but may include conventional plain paper, art paper, coated paper, and the like. Sheets and films of vinyl chloride resin, polyester resin, and polyolefin resin, synthetic paper, laminated paper, and the like can be used. It may be a three-dimensional object.

The same effect can be obtained when the support contains a laser shielding agent, provided that the content is sufficient.
The method of including the laser shielding agent in the support depends on the method of manufacturing the support.For example, in the case of paper, in a liquid for performing normal papermaking, in an art paper or a coated paper, in a liquid to be coated, By dispersing or dissolving the laser shielding agent by an appropriate general method, paper making or coating is performed, and paper, coated paper, art paper, etc. containing the laser shielding agent can be produced.

In the case of a plastic film, in the process of manufacturing the film by T-die extrusion or the like, the film is formed into a film together with a resin to be formed into a film or together with a resin containing a laser shielding agent at a high concentration in advance. Good. The thickness of the support is not particularly limited.

As a method for forming the shielding layer or the laser coloring layer on the support, a special method is not required for forming the layer, and a conventional coating method can be used. For example, gravure printing, Coating methods such as offset printing, flexographic printing, screen printing, air knife coating, blade coating, and die coating are exemplified.

The coating thickness of the shielding layer is 0.1 to 20 after drying.
g / m ² or 0.1 to ²⁰ μm, preferably 0.5 to
10 g / m ² or 0.5 to 10 μm. The material forming the layer is a fixing agent composed of a resin component suitable for these coating methods, a laser shielding agent is present in the case of a layer containing a laser shielding agent, and a thermochromic pigment in the case of a laser coloring layer. A coloring agent such as a leuco dye or a developer is dispersed or dissolved in particles. In order to enhance the shielding effect, the laser coloring layer may contain the aforementioned laser shielding agent.

Examples of the resin component of the shielding layer containing the laser shielding agent include polyamide resins, polybutyral resins, polyvinyl butyral resins, polyvinyl alcohol resins, nitrocellulose resins, acrylic resins, and vinyl chloride-vinyl acetate. There are polymer resins, urethane resins, petroleum resins, chlorinated rubber resins, cyclized rubber resins, alkyd resins, phenolic resins, epoxy resins, etc., and these resin components are more suitable for the coating method at the time of coating. It is used after being dissolved or dispersed in an organic solvent or water. Further, drying or curing may be performed by a method such as heat or energy ray without solvent.

In the shielding layer containing the laser shielding agent, if necessary, for example, calcium carbonate, silica, alumina,
Fillers such as magnesia, titania, barium sulfate, and zinc oxide, and coloring agents such as pigments and dyes can be added.

The content of the laser shielding agent in the dried coating film of the shielding layer containing the laser shielding agent is preferably as large as possible within the range that can be applied, and is 5 to 90 wt%, preferably 20 to 70 wt%.
% Is good.

The coating thickness of the shielding layer is 0.1 to 20 after drying.
g / m ² or 0.1 to 20 μm, preferably 0.1 to
10 g / m ² or 0.1 to 10 μm. The thicker the coating film, the higher the shielding effect. If the coating thickness is large, the content of the laser shielding agent can be reduced.

If necessary, the shielding layer may be formed of two or more layers. Further, a colored layer may be formed at an arbitrary position on the recording medium to improve the function as the recording medium.

The recording material for laser marking of the present invention includes:
In order to increase the durability or suppress damage due to external force, polyethylene resin, polypropylene resin, ethylene-vinyl acetate resin, ethylene-ethyl acrylate resin, acetate nitrocellulose resin,
Nitrocellulose resin, polyamide resin, acrylic resin, polyurethane resin, polyester resin, epoxy resin, silicone resin, fluorine resin, etc. An overcoat layer made of a material to which an auxiliary agent such as an agent, an antioxidant, a water repellent, or an oil repellent is added can be formed on the laser coloring layer.

The addition of an ultraviolet absorber or an antioxidant to the overcoat layer suppresses deterioration of the display due to light or heat,
Increase the long-term storage of the display. The coating liquid for the support, the shielding layer containing the laser shielding agent, and the laser coloring layer includes a dispersant,
Viscosity modifiers, fillers, leveling agents, lubricants, ultraviolet absorbers, antioxidants, antistatic agents, coloring agents, heat shielding agents,
Auxiliaries classified as preservatives and the like can be added.

[0036] To implement the method of the present invention may be marked by irradiating a carbon dioxide laser beam to the laser marking recording medium of the present invention, as a laser device, the output is 0.2 Joules / cm ² · Pulse or more, preferably 0.3
Joules / cm ² · pulse or more energy given pulse type carbon dioxide gas laser irradiation surface, or output 0.5W
Preferably Scanning carbon dioxide lasers having the above output,
Above all, Transversely Excited
Atmospheric Pressure (TE
Since the A) type carbon dioxide laser can irradiate a wide area with a single pulse at a high speed, it is particularly preferable because a large amount of information can be marked at a high speed.

[0037]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but it should not be construed that the invention is limited thereto. The parts and percentages in the examples are on a weight basis.

[Coloring Ink I] 2- (2-chlorophenylamino) -6-diethylaminofluoran [TH-106, manufactured by Hodogaya Chemical Co., Ltd.] 15 parts Gallic acid n-propyl ester 8 parts Methanol solution containing 20% polyamide resin 54 Part [AQ-Nylon K-80 manufactured by Toray Industries, Inc.] 20% aqueous solution of ammonium nitrate 8 parts Muscovite 15 parts (diluent solvent: methanol)

[Coloring ink II] 2,2-bis [4- [6 '-(N-cyclohexyl-N-methylamino) -3'-methylspiro [phthalide-3,9'-xanthene] -2'- Ilamino] phenyl] propane 8 parts 3,4-dihydroxyphenyl-4'-methylphenylsulfone 5 parts Zinc borate 6 parts Polyamide resin [Toray K-80] 3 parts Ammonium chloride saturated aqueous solution 5 parts Ethanol 23 parts

[Laser shielding white ink formulation A] 100 parts of a methanol solution containing 20% of a polyamide resin [Toresin F-30 manufactured by Teikoku Chemical Industry Co., Ltd.] 40 parts of a laser shielding agent

[OP varnish] OP varnish for nitrocellulose gravure printing [SF815 manufactured by Dainippon Ink and Chemicals, Inc.] (diluent solvent: ethyl acetate)

The dispersion of the color-forming ink and the laser shielding white ink A was prepared by shaking a prescribed formulation together with glass beads in a paint conditioner for 3 hours. The laser-shielded white ink formulation A was applied to a base paper with a Meyer bar to a dry coating film of about 3 g / cm ² . A color developing ink prepared by adding a diluting solvent so that the viscosity becomes 18 ± 1 seconds in a viscosity measurement using a # 3 Zahn cup was printed thereon using a helio gravure plate of 70 lines / cm. Next, an OP varnish was printed on the coloring ink in the same manner as the coloring ink to prepare a recording medium for evaluation. Base paper is about 2μ on clay coated paper.
m was used.

Laser marking on the produced recording medium is as follows.
Using a TEA-type carbon dioxide laser irradiator manufactured by Shibuya Kogyo Co., and irradiating one pulse of a laser beam having an irradiation energy density of 0.40 to 0.70 Joules / cm ² · pulse through a metal mask cut into a letter shape. Printed. The laser shielding effect was evaluated by examining the prominence of the printed portion by touching with a finger.
The effect of the laser shielding layer is more excellent and useful as the recording medium does not rise even when irradiated with a laser having a high energy density. The laser chromogenic irradiates a laser beam of 0.4 J / cm ² (Joules / cm ²⁾ and 0.6 J / cm ² on the recording material was evaluated by visual observation of the visibility. The better the visibility at 0.4 J / cm ² , the more sensitive and useful.

Incidentally, the laser irradiation energy density is determined by the detector number of the model No. E manufactured by GENTEC Inc.
D-500} was installed, and this was irradiated with one pulse of carbon dioxide laser light. After reading the total irradiation energy obtained by converting the output voltage of the detector with a laser energy meter {GENTEC Model No. EM-1}, This measured value is divided by the area of all the laser beams on the irradiation surface to obtain a unit area of 1
The irradiation energy density per pulse was determined.

Examples 1 and 2 and Comparative Examples 1 to 5 The laser recording agents shown in Table 1 were adjusted with the blending of the laser shielding white ink A, and the applied color ink layer and OP varnish layer were printed for evaluation. Table 1 shows the results of laser printing on the body.

Comparative Example 6 A recording medium was obtained in the same manner as in Example 1 except that the laser shielding ink was not applied, and laser printing was performed in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 7 A recording medium was obtained in the same manner as in Example 1, except that a laser shielding ink using titanium oxide was used instead of the laser shielding agent (titanium oxide-coated mica). Laser printed. Table 1 shows the results.

[0048] In Example 3 Example 2, except that 50% of the amount of laser blocking agent was replaced by titanium oxide in the same manner to adjust the laser shielding white ink, to obtain a recording material, in the same manner as in Example 2 Laser printing. Table 1 shows the results.

[0049]

Description of Compounds Used in Tables Titanium oxide-coated mica: Iriodin 100 manufactured by Merck Ltd. (average particle size: 4.6 μm) Fluorosilicon mica: Micromica MK-100 manufactured by Corp Chemical Co., Ltd. (average particle size: 3) .6 μm) Muscovite: Mica powder A21 (average particle size: 11 μm) manufactured by Kirara Co., Ltd. Kaolin clay: ASP17 manufactured by Tsuchiya Kaolin Industries, Ltd.
0 (average particle size: 1.5 μm) Aluminum powder: Dry paste P1100 manufactured by Toyo Aluminum Co., Ltd. (average particle size: 22 μm) Titanium oxide: JR-801 manufactured by Teica Co., Ltd. (average particle size: 0.5 μm)

[0051]

[Table 1]

1. Laser shielding performance ×: The base paper is raised at 0.50 J / cm ² or less ○: The base paper is raised at 0.55 to 0.65 J / cm ² ◎: 0.65 J / cm ² raised of the base paper does not occur 2. laser chromogenic ×: laser color is thin, low visibility ○: with sufficient laser color, visibility good

Example 4 The recording medium of Example 3 was replaced with coloring ink instead of coloring ink I.
A recording medium label was obtained in the same manner except that II was used.
Printing was performed by irradiating one pulse of carbon dioxide laser light of joule / cm ² . Next, an evaluation solution having the following composition was prepared, applied to a laser-printed label with a sponge, and further immersed in water at 30 ° C. for 12 hours to measure the lightness of the laser-colored portion to determine chemical resistance (printing durability). evaluated. As a result of the test, the lightness before immersion was 47 and the lightness after the chemical resistance test was 52. The decrease in the lightness was as small as less than 10, and the laser printing of a sufficient density was maintained visually, indicating high chemical resistance.

Composition of Chemical Resistance Evaluation Solution Isopyryl myristate 20 parts Isopropyl palmitate 10 parts Capric acid triglyceride 45 parts Sorbitan sesquiolate 6 parts Polyoxyethylene nonylphenyl ether 6 parts Polyoxyethylene (20) sorbitan oleate 3 parts Silicone oil 10 parts (Toshiba Silicone TSF451-350)

[0055]

According to the recording material for laser marking having the laser shielding layer of the present invention, a low energy density carbon dioxide gas
Laser coloration occurs even with laser irradiation, resulting in energy efficiency
Better marking at higher speed or wider printing area
In addition, in laser marking, it is possible to prevent the laser beam from damaging the base paper of the recording medium or the product under the recording medium from being damaged, so that the product name, lot number, code, expiration date, etc. It is particularly suitable for online marking of labels, nameplates, cards, containers and the like that require printing.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI B41M 5/18 101D (72) Inventor Teruhito Isonaga 2-10-1 Shinkawa, Chuo-ku, Tokyo Kirin Brewery Co., Ltd. (72) Invention Person Tadashi Kobayakawa 2-10-1 Shinkawa, Chuo-ku, Tokyo Kirin Brewery Co., Ltd. (56) References JP-A-2-204087 (JP, A) JP-A-2-120082 (JP, A) JP-A Sho 54- 23547 (JP, A) JP-A-54-4142 (JP, A) JP-A-7-96673 (JP, A) JP-A-6-166266 (JP, A) JP-A-5-57463 (JP, A) JP-A-58-134791 (JP, A) JP-A-58-145493 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/26-5/34 B23K 26/00 G09F 3/00 G09F 3/02

Claims (8)

(57) [Claims] 1. A shielding material comprising a laser shielding agent on a support.
In a recording medium having a shielding layer and further having a laser coloring layer on the shielding layer , the laser shielding agent is coated with titanium oxide.
Carbonic acid characterized by being mica or tetrasilicon mica
Gas laser marking for the recording medium. 2. The recording medium according to claim 1 , wherein the shielding layer contains a laser shielding agent at a content of 5 to 90% by weight. 3. A recording material according to claim 1 or 2 the thickness of the shielding layer is 0.1 to 20 [mu] m. 4. A recording material according to any one of the laser coloring claim 1 overcoat layer for protection is formed on the upper layer of the layer 3. 5. The recording medium is a label for display.
4. The recording medium according to any one of 4 . 6. A shielding containing a laser shielding agent on a support.
Has蔽層, further on top of the shielding layer, the recording material having a laser coloring layer was irradiated with letters and / or carbon dioxide laser light for displaying or recording the shape, the laser coloring layer discolored by heat In the laser marking method for performing marking by laser, the laser shielding agent is a titanium oxide-coated mica or fluorine.
Laser marking method which is characterized in that it is a Motoyon silicon mica. 7. The method according to claim 6 , wherein a protective overcoat layer is formed on the laser coloring layer. 8. The recording medium according to claim 6 , wherein the recording medium is a display label.
Is the method described in 7 .