JP2504692Y2 - Laser marking laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a laser-markable and markable laminate, and more particularly to a label material laminated with a plastic film based on an aluminum foil.

[Prior Art] With the progress of packaging technology, many materials have been used in the field of packaging materials, and metal cans, plastic films, laminated bottles, cans, glass bottles, along with the integrity of packaging, automation of packaging, and beauty of packaging products. Many other containers are used.

These containers, etc. are provided with pictures and patterns showing the image of the product, and labels to show the contents and the manufacturer's name.These labels also have the lot number of the product, the date of manufacture, etc. printed on them. ing. In the early stages, these markings used ink, hot stamping, embossing, etc. on the packaging line.

However, in recent years, laser marking has begun to be adopted in view of the speeding up of packaging lines, the permanent disappearance of printed marks, the inability to change marks, and the demand for finer marking marks.

On the other hand, as the label material, a label material based on aluminum foil is often used from the viewpoint of productivity, beauty of printing, cost, and ease of handling, and a container for lactic acid beverage or the like sealed by heat bonding. It is often adopted that a material obtained by laminating a plastic film and an aluminum foil is used for the lid material and printing is directly performed on the lid material.

In such a field, the aluminum foil is of a type in which a colored coating is directly applied and the coating material is marked with a laser to expose the aluminum foil.

However, since the aluminum foil has a strong metallic luster, the reflection is strong and the mark is difficult to read.

[Problems to be Solved by the Invention] The present invention is directed to a laminate mainly composed of aluminum foil (in the present specification, a laminate of aluminum foil and plastic, such as a label, a lid material, a bag using the laminate, etc. It will be collectively referred to as a label hereinafter), and its purpose is to develop a label material that can be clearly marked by laser printing.

[Means for Solving the Problems] The present invention has developed a label that enables more vivid marking on the printed surface of the aluminum foil itself, rather than the metallic glossy surface of the aluminum foil, which has strong gloss when marking by laser printing. It was done.

That is, a colored plastic film and an aluminum foil that is printed in a different color tone from this and has an adhesive layer or adhesive layer for adhering or sticking to the adherend on the other surface The present invention relates to a label for laser marking, which is characterized in that it is pasted with an agent.

In the present invention, the colored plastic film means both a plastic film colored by printing or, in the case of a monochromatic film, a film itself manufactured from a colored resin.

When printing, there is an advantage that partial color changes and patterns can be freely selected. On the other hand, if a single color is acceptable, use a colored film to reduce costs,
Man-hours can be reduced.

In this case, the material of the plastic film is not particularly limited, as long as stains do not remain on the remaining portion by laser printing, for example, biaxially stretched polyethylene terephthalate, polypropylene, polyamide or the like film, the thickness is Although not particularly limited, about 10 μm is convenient for use. A urethane type ink can be preferably used as the ink.

The printing of the aluminum foil which has been printed and provided with an adhesive layer or an adhesive layer for adhering or sticking to the adherend on the other surface may be printing on the entire surface or printing only on the marking portion. The point is that the printed plastic or colored plastic film on the surface is evaporated (volatilized) by the laser to expose the printed surface, and the aluminum foil surface should not be exposed.

In this case, if the color tone is selected to be opposite to that of the printed plastic on the surface, the marking can be clearly read and read.

Since the surface of this printing surface is vaporized (volatilized) by a laser, it is better to be a little thicker than thin, and the ink material is preferably selected from pigments and resins that do not easily change even when exposed to a small amount of laser.

As the ink, a vinyl chloride-based or vinegar-based ink can be sufficiently used. The area and place should be selected according to common sense.

The adhesive layer or pressure-sensitive adhesive layer on the other side of the printing surface is a hot-melt adhesive or pressure-sensitive adhesive that is usually used for aluminum foil for packaging.

The printed surface of the plastic film and the printed surface of the aluminum foil are bonded to each other with an adhesive. In this case, the adhesive is relatively transparent and has a thickness of 4 to 5 μm, which is suitable for marking with laser light. is there. It seems that the adhesive serves to bond both sides and protect the printed surface of the aluminum foil when it is irradiated with laser light.
A preferable example is a two-component curing type urethane adhesive for dry lamination.

Most of the lasers used are carbon dioxide lasers, and when the label is irradiated with a laser beam, the plastic film on the surface, a part of the printing and adhesive layer on it (which may be the entire case). Evaporation (volatilization)
Then, the printed surface of the aluminum foil will be exposed.

The structure of this label is shown in the drawing: plastic film 1, its printing layer (about 1 to 3 g / m ² ) 2, adhesive 3, printing layer 4 on aluminum foil, aluminum foil 5 and adhesion or adhesion to the adherend An adhesive layer or a pressure-sensitive adhesive layer 6 is provided for the purpose.

[Function] Laser marking may be performed before or after adhesion to the adherend, but this strength is
The preferred range varies depending on the thickness of the printing layer, adhesive layer, etc.,
This can be easily tested and selected.

When the label surface is irradiated with laser light of appropriate intensity,
The plastic film and the printed surface evaporate (volatilize), and the printed surface of the aluminum foil passes through the transparent adhesive layer or the printed surface is exposed to form a clear marking.

[Example] Biaxially stretched polyethylene terephthalate film 12 μm
Prepared by printing white urethane ink at a thickness of ² g / m ² on the other hand, and printing vinyl chloride / vinyl acetate black ink at a thickness of ² g / m ^{2 on} a 20 μm thick aluminum foil. 4μ
It was adhered by a two-component curing type urethane adhesive for dry lamination having a thickness of m. When this was marked using "Laser Brand Marking System" (made by EDM Co., Ltd.), a black mark could be clearly printed on a white background.

[Effects of the invention] When marking with laser light, high-speed marking is possible, it does not disappear permanently, and the marks can be made finer, and problems such as ink stains and cleaning such as ink jets can be solved. It was However, when applied to simply printed aluminum foil, there was a problem that even fine print was difficult to read due to the metallic luster of aluminum itself, but when using the label of the present invention, all the advantages of conventional marking with laser light were taken. It is possible to obtain an advantage that the printing is clear while it is held, and the background color and the coloring of the printing can be freely selected.

[Brief description of drawings]

FIG. 1 is a sectional view showing one construction of the label of the present invention. 1. Plastic film, 2. Printing layer 3. Adhesive layer, 4. Printing layer 5. Aluminum foil 6. Adhesive layer or adhesive layer

Claims (2)

(57) [Scope of utility model registration request] 1. A colored surface comprising a colored plastic film and an aluminum foil printed in a color tone different from that of the plastic film and provided with an adhesive layer or an adhesive layer for adhering or sticking to an adherend on the other surface. A laminate for laser marking, which is characterized in that the two are stuck together with an adhesive. 2. Coloring of a printed plastic film in a color tone different from that of the coloring of the film, and coloring of an aluminum foil having an adhesive layer or an adhesive layer for adhering or sticking to an adherend on the other surface. A laminated body for laser marking, which is characterized in that the laminated surface is adhered to the formed surface with an adhesive.