JP2722285B2 - Secret sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secret sheet having hidden information such as characters and figures, which can be peeled off to view the information.

[0002]

2. Description of the Related Art At present, a representative example of a secret sheet most widely used is a postcard sent from a credit or insurance company to a customer. Information to be transmitted to the customer is printed on the back of the postcard. An concealing label is attached from above to conceal this information. The concealing label is formed by pseudo-adhering a transparent polyester film having a pressure-sensitive adhesive layer applied to one side of a label paper via a polyethylene layer. The concealment label is attached to the back of the postcard by the adhesive layer on polyethylene, but when peeling it off, the concealment label leaves the polyester film on the postcard side by adhesion by the adhesive layer, and removes it from the polyethylene layer. It can be conveniently separated and hidden information can be seen from outside through a transparent polyester film.

[0003]

The above-described structure of the secret sheet requires a technique of pseudo bonding of the film,
The production thereof requires special equipment and has a drawback that the cost is increased as a result, and there has been a strong demand for an inexpensive and simple secret sheet instead of this. The present invention has been developed to satisfy such a demand, and an object of the present invention is to provide a new and useful secret sheet by applying conventional adhesive paper and / or adhesive paper.

[0004]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
It consists of a combination of paper made by attaching thin paper to an adhesive layer applied to a paper support, and coated paper coated with an adhesive layer,
Printing information such as characters and figures on the thin paper surface of the paper,
This is achieved by providing a secret sheet, which is described by handwriting or the like and is characterized by laminating the coated paper on thin paper of the paper via an adhesive layer.

[0005]

When the coated paper is to be peeled off from the paper support in the secret sheet having the above structure according to the present invention, the peeling is caused by delamination of the thin paper. That is, since the thin paper is adhesively bonded on both sides to the adhesive, when separating the coated paper and the paper support from each other,
Both layers are pulled almost equally, causing delamination. By the way, printing on the surface of thin paper, handwriting (by ballpoint pen)
Is performed, the ink soaks into the thin paper layer by capillary action. Thus, when the thin paper is separated into two pieces by delamination, the hidden information is present in the thin paper portion remaining on the paper support by ink seepage, and the information can be read.

[0006]

FIG. 1 is a cross-sectional view of a secret sheet according to the present invention before lamination. A paper 1 has an adhesive layer 3 applied on a paper support 2 and an adhesive layer 3 adhered to the adhesive layer 3. And thin paper 4 attached thereto. The thin paper 4 preferably has a very thin paper layer such as tissue paper and has a smooth surface from the viewpoint of ink permeability and printing characteristics. The coated paper 5 is formed by applying an adhesive layer 6 on the lower surface thereof,
The pressure-sensitive adhesive layer is usually covered with a protective paper 7 subjected to a release treatment. It will be noted that the paper support 2 and the coated paper 5 coated with the adhesive layer of the paper 1 are nothing but so-called conventional adhesive papers. Therefore, in forming the secret sheet according to the present invention, such an adhesive paper can be used as it is.

When using a secret sheet,
The required hidden information is printed or handwritten on the thin paper 4 of the paper 1, the protective paper 7 is peeled off, and the coated paper 5 is bonded with the adhesive layer 6. At an appropriate time, the information is hidden by the covering paper 5. FIG. 2 shows a state in which the coated paper 5 is attached to the thin paper 4 of the paper support.

FIG. 4 shows the same paper 1 as shown in FIG.
3 shows a secret sheet including a coated paper 5 on which a hot-melt adhesive layer 6 is formed instead of a pressure-sensitive adhesive layer. In this example, of course, it is not necessary to cover the adhesive surface with protective paper. When the hidden information is printed or handwritten on the thin paper 4 in the same manner as described above, and the coated paper 5 is overlaid thereon and heated, the adhesive layer 6 is activated and adhered to the thin paper 4. become.

In the secret sheet, to facilitate stripping of the coated paper 5, for example, as shown in FIGS. 1 to 4, the coated paper 5 is cut along one edge thereof, that is, slits 8 are formed. Is good.

[0010] Thus, when the coated paper 5 is to be peeled from the paper support 2, the peeling is caused by delamination of the thin paper 4. That is, since both sides of the thin paper 4 are adhesively bonded to the adhesive, when the coated paper and the paper support are to be peeled off from each other, the thin paper 4 is pulled almost equally by both of them and causes delamination. When the thin paper is separated into two parts 4a and 4b by delamination, the printing and handwriting (by a ballpoint pen) made on the surface of the thin paper are soaked into the paper layer of the thin paper by capillary action. As shown in FIG. 3, the hidden information is present in the thin paper portion 4a remaining on the paper support due to the ink impregnation 9 and the information can be reliably read.

In this type of secret sheet, it is required that the hidden information cannot be recognized even if it is watermarked while the coated paper is pasted on the paper.
As one of the countermeasures, it is preferable to prevent the transmission of light by mixing aluminum powder into the adhesive applied to the coated paper. Further, as another example, a concealing pattern exhibiting concealment of information may be printed on the pressure-sensitive adhesive layer side of the coated paper in advance, or aluminum may be deposited.

[0012]

As described above, the secret sheet according to the present invention has an extremely simple structure in which extremely thin paper is bonded to the adhesive paper, so that the conventional bonding technique can be used in the production thereof. As a whole, an inexpensive secret sheet can be provided. In addition, the secret sheet according to the present invention can be used not only as a postcard that allows a credit, an insurance company, or the like to inform a customer of hidden information, but also can be used as a tag for various kinds of winning lottery and delivery processing.

[Brief description of the drawings]

FIG. 1 is a sectional view of a secret sheet according to the present invention before laminating.

FIG. 2 is a cross-sectional view of a secret sheet according to the present invention in which protective paper, that is, release paper is peeled off and bonded.

FIG. 3 is a perspective view of the secret sheet according to the present invention in a state where the coated paper is peeled off.

FIG. 4 is a view similar to FIG. 1 of another example of a secret sheet according to the present invention.

[Explanation of symbols]

1 Paper 2 Paper supports 3 adhesive layer 4 thin 5 coated paper 6 viscosity Chakuzaiso 7 protective sheet

Claims (6)

(57) [Claims] 1. A combination of a paper in which thin paper is adhered to an adhesive layer applied to a paper support and a coated paper in which an adhesive layer is applied, wherein characters, graphics, etc. are formed on the surface of the thin paper of the paper. The secret sheet is characterized in that the information is described by printing, handwriting, or the like, and then the coated paper is bonded to the thin paper via the adhesive layer. 2. The secret sheet according to claim 1, wherein the adhesive layer applied to the coated paper is made of an adhesive, and a protective paper subjected to a release treatment is bonded to the adhesive layer. 3. The secret sheet according to claim 1, wherein the adhesive layer of the coated paper is made of a hot melt type adhesive. 4. The pressure-sensitive adhesive layer of the coated paper is mixed with aluminum powder in order to secure concealment of information on the thin paper when the paper is laminated on the thin paper. The secret sheet according to. 5. A concealing pattern is printed on the back surface of the coated paper to secure concealment of information on the thin paper when the paper is laminated on the thin paper.
The secret sheet according to. 6. The backside of the coated paper is coated with aluminum to secure the concealment of information on the thin paper when the paper is laminated on the thin paper.
The secret sheet according to any one of the above.