JPS61197285A - Print - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printed matter in which the printed surface can be protected by making the printed content visible from the back surface.

[Conventional technology]

In the past, printing generally involved creating a mold from a suitable master plate and transferring the ink applied to the mold onto a suitable paper, etc.; Techniques have been developed to print directly onto paper or the like without the need for printing.

For example, the so-called inkjet printing method is a printing technique in which ink is directly jetted from a nozzle onto paper, etc., and the amount and pattern of the jetting is controlled by a computer, so it is a simple printing technology that does not require original plates or molds, and is particularly popular. It is suitable for printing relatively small quantities of a wide variety of items, such as posters and restaurant menus.

[Problem that the invention seeks to solve]

However, the posters and restaurant menus mentioned above,
Printed content may become unclear due to contact with many people's hands, so it is necessary to protect the printed surface by some means, but conventional methods include laminating, vinyl coating, or transparent covers. The problem was that it required time and cost for processing.

[Means for solving problems]

The present invention has been made with the aim of solving the above-mentioned problems of the prior art, and is constructed by laminating a porous surface layer on one side of a transparent or nearly transparent support made of a transparent plastic film or the like. The printed content is made visible from the support side by appropriately printing on the base paper from the surface side using highly permeable ink using an inkjet printing method or the like. It is.

That is, the inventors of the present invention have realized that if paper or the like is printed and used so as to be viewed from the back side, there is no need to specially protect the printed surface, and the above-mentioned difficulties can be solved economically. We focused on the image-receiving paper used in conventional inkjet printing, but the ink does not penetrate sufficiently into the inside of the paper, making it impossible to see the printed content from behind the printed surface. By diligently continuing experimental research on this image-receiving paper, we were able to complete the present invention.

The reason why conventionally used image-receiving paper has poor ink permeability is that paper made using the papermaking method has intertwined fibers that spread horizontally, causing the ink to diffuse horizontally. This is because if a sizing agent is used to suppress the tendency, the penetration in the vertical direction will be reduced and the color density on the back side will be reduced. This is thought to be because the resin containing the agent is formed into a sheet shape and then stretched to make it porous, so the formed pores become longer in the direction of the paper, giving priority to penetration in the lateral direction.

Next, the present invention will be explained in detail.

The base paper used for the printed matter of the present invention is basically constructed by laminating a porous surface layer on a suitable transparent or nearly transparent support, and this support is coated with a transparent plastic film, such as polyester. A synthetic resin film such as a film or a polystyrene film can be used, and the thickness thereof is not particularly limited.

On the other hand, the porous surface layer formed on this support is composed of components such as a binder resin such as polyester, a filler such as titanium oxide or calcium carbonate, and a plasticizer such as dioctyl adipate. To apply it onto the support, prepare a coating solution by dispersing any of the above components in a dispersion medium such as dimethylformamide, apply the coating solution on the support, and then introduce it into water. Either a wet method in which the coating solution is coagulated using water or a dry method in which the coating solution using a dispersion medium such as water is coated on a support and then dried can be employed.

Note that the thickness of this surface layer can be varied as appropriate;
It has been found that it is 5μ or more, preferably 10μ or more.

There are various ways to print from the surface side of the base paper obtained in this way, but for example, the inkjet printing method described above is preferred because it is simple, and the ink used in this printer is highly permeable. be used.

It goes without saying that the printing means is not limited to the above inkjet printing method.

[Effect]

When producing the printed matter of the present invention by the process described above, when the base paper is printed with a highly permeable ink, the ink immediately penetrates through the surface layer and reaches near the support on the back side. The printed matter has a high color density on the back side, and this is thought to be due to the structure of the surface layer formed on the support.

That is, when a dispersion containing resin etc. is applied and coagulated in water or dried in air, the resin separates from the liquid to form small spheres (coacervation).
As the coagulation and drying further progresses, the globules become connected open cells, with cracks forming on the surface and a structure in which they are connected to the support with small gaps, and because of this structure, the ink does not reach the vicinity of the support. It is thought that it will penetrate.

〔effect〕

Therefore, in the printed matter of the present invention, even if the inkjet printing method 1~, which originally has a low ink concentration, is used, the open cells are filled with ink, making it difficult to view the printed matter from the back side or to detect the vA using transmitted light. This makes it possible to visually recognize the contents of the print extremely clearly.

〔Example〕

Next, embodiments of the present invention will be described in detail.

50μ of a coating solution consisting of 100 parts of polyester (binder resin), 300 parts of dimethylformamide (dispersion medium), 20 parts of dioctyl adipate (plasticizer), 20 parts of titanium oxide (filler), and 180 parts of calcium carbonate (filler) The polyester sheet was coated on a support with an anchor coating, immersed in water for 1 minute, then immersed in 80°C hot water for 5 seconds, taken out and air-dried to form a 30μ thick surface layer.

When printing was performed on an example of the obtained base paper using an inkjet printer from the surface layer side, it was confirmed that the ink was absorbed to the back surface near the support.

Example 2 Latex (binder resin) 150 parts Water (dispersion medium) 6
0 parts titanium oxide (filler) 10 parts surfactant 05 parts ammonia water 0.5 parts pearlite powder
5 parts of a coating solution with a composition of 60 parts
It was coated on a support made of a 0μ polypropylene sheet coated with Anchor Coat 1-.

After being heated and dried, it was taken out and air-dried to form a surface layer with a thickness of 15 μm.

When the obtained base paper was printed separately from the front side using an Infusiera 1-printer, it was observed that the ink was absorbed to the back side near the support.

When printing was performed using an inkjet printer on high-quality paper with an average f of 180 g/m, the ink did not reach the back surface.

Differences between the printed matter of "Tsubuiguchi row" 2 and the comparative example The printed matter of the present invention obtained in Examples 1 and 2 above and the printed matter of the comparative example were
Color reflection densitometer manufactured by Dainippon Screen (DM-400)
) was used to measure the ink density on the printed side and back side, and the results shown in the table below were obtained.

Since the present invention is as described above, it is extremely excellent in that the printed content can be visually recognized from the back side.

Claims (1)

[Claims] On a base paper formed by laminating a porous surface layer on one side of a transparent or nearly transparent support such as a transparent plastic film, appropriate printing is performed using highly permeable ink using an inkjet printing method or the like from the surface layer side. A printed matter characterized in that the printed content is made visible from the support side by performing the following steps.