JPH04107186A - Transparent printing sheet - Google Patents

Abstract

PURPOSE:To provide excellent ink setting, ink drying properties, ink adherence for various printings by coating a base material of a transparent plastic film with coating solution containing emulsion of vinyl acetate-ethylene-acrylic copolymer resin or/and vinyl chloride-acrylic copolymer resin as a main ingredient to provide an ink fixing layer. CONSTITUTION:As a plastic film as a base material, a transparent polyolefin film such as polyethylene film, polypropylene film, etc., is, for example, employed. A moldable transparent film such as nonoriented polyester film, a transparent vinyl chloride film, etc., is used to be molded after printing. Components for constituting an ink fixing layer include, for example, vinyl- acetate-ethylene-acrylic copolymer resin or vinyl-chloride-acrylic copolymer resin, or which may be mixed. As a method of mixing the components, mere mixing or agitating is executed to prepare coating solution. The resins of these types are employed to improve ink setting properties.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention not only can be printed with ordinary drying oil type ink as a film for various cards, labels, overhead projectors, etc. The present invention relates to transparent printing paper that can be recorded by various printers, and can also be used as various printable packaging materials by using a moldable film as the base material.

[Conventional technology]

Plastic films generally have excellent transparency, processability, mechanical strength, light resistance, weather resistance, chemical resistance, etc., but when printing on them, special inks suitable for each film must be used. Not only that, but the printing method is also limited.

[Problem to be solved by the invention]

That is, with plastic films, the drying and curing of ink is extremely slow, making it difficult to print with ordinary ink. For this reason, some plastic films have been created with a porous modified layer on their surface to give them ink absorbency and make printing easier, but this has the problem of reducing transparency. .

In addition, in recent years, recording methods such as printing have become more diverse, but the above-mentioned plastic film with a porous modified layer formed on its surface cannot be used with all recording methods. Herad projector (OHP)
In order to be able to use it as a film for printing, it is desirable to have a transparent and printable plastic film, and also a transparent printing paper that can be used for offset printing, which is the mainstream of general printing today. If developed, it would be extremely useful.

Therefore, the problem to be solved by the present invention is to
It is an object of the present invention to provide a transparent printing paper that can be used not only as a commercial film but also for various types of printing including offset printing, recording by wire dot printers, thermal transfer printers, etc., and furthermore, can be used as various packaging materials.

[Means to solve the problem]

The present invention was made with the aim of solving the above problems, and has a structure in which vinyl acetate-ethylene-acrylic copolymer resin or/and vinyl chloride is used on at least one side of a base material made of a transparent plastic film. - It is characterized in that an ink fixing layer is provided by applying a coating liquid whose main component is an emulsion of an acrylic copolymer resin.

That is, the present invention improves ink fixability, in other words, ink adhesion (wetting), by modifying the surface of the film.
The present invention provides transparent printing paper that has good absorbency and dry hardening properties, can be applied to many types of recording media, and also has excellent scratch resistance, stain resistance, slipperiness, etc. that are generally required for printing paper. be.

In addition, by using a moldable film as the base material,
It can also be used as a variety of packaging materials, and by making it into a packaging material with printing, it is possible to increase the commercial value of the packaged product.

Next, the present invention will be explained in detail.

The plastic film used as the base material may be transparent as long as it is transparent1. Examples include polyolefin films such as polyethylene films and polypropylene films, polyester films, polycarbonate films, triacetate films, polyether sulfone films, vinyl chloride films, and methyl methacrylate. There are various types of acrylic films and cellophane films.

Among these, polyester film, vinyl chloride film, polypropylene film or triacetate film is preferred. These plastic films may be treated in advance to improve their adhesion to the ink fixing layer.

Further, by using a moldable transparent film such as an unstretched polyester film or a transparent vinyl chloride film, molding after printing becomes possible.

The components constituting the ink fixing layer are vinyl acetate-ethylene-acrylic copolymer resin or vinyl chloride-acrylic copolymer resin, and these may be used in combination.

By using these types of resins, ink setting properties are improved. If blocking occurs when using these resins, it is effective to add colloidal silica. Colloidal silica has a particle size of 5 mm to 10 mm.
By adding this colloidal silica, which is a colloidal liquid in which fine spherical silica of 0 mm μ dust is dispersed in water, heat blocking properties, moist heat blocking properties, scratch resistance, antistatic properties, etc. are also improved. The amount of colloidal silica added must be within a range that does not impair transparency.

As a method of mixing these components, a coating liquid can be prepared by simply mixing and stirring. It may also be a colloidal silica composite particle emulsion.

As mentioned above, the main component of the ink fixing layer is vinyl acetate.
Ethylene-acrylic copolymer resin and/or vinyl chloride-acrylic copolymer resin, as needed for purposes such as further improving scratch resistance.

Other resin components (for example, polyester resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinyl alcohol, cellulose derivative, melamine resin, isocyanate crosslinked resin) may be mixed. Furthermore, in order to improve film runnability during offset printing, a trace amount of filler such as silica powder may be mixed within a range that does not impair transparency.

[Action of the invention]

Since the transparent printing paper of the present invention is provided with the above-described ink fixing layer on one surface, it has good printing ink setting properties, ink drying properties, and ink fixing properties.

In general, ink setting affects high-speed printing and efficiency, and even if you can print beautifully, if the printing speed is slow due to set-off and you cannot stack printed materials, economical printing will be impossible. However, in the printing paper of the present invention, the ink is strongly retained in the ink fixing layer on the surface of the film, and the solvent component in the vehicle is absorbed by the ink fixing layer, increasing the viscosity of the ink sufficiently, making it difficult for the ink to set. fast,
Even if films are stacked with incomplete drying and curing due to oxidative polymerization of drying oil, set-off will not occur.

By mixing colloidal silica with the coating film component constituting the ink fixing layer, when the coating film component is dried and formed into a film, the hydroxyl groups of the colloidal silica are dehydrated and condensed with each other, forming siloxane bonds 5i-O-5i. to form a strong three-dimensional network structure.

Therefore, the hardness of the coating film on the surface of the ink fixing layer increases and the scratch resistance improves. Furthermore, since colloidal silica is mixed in the ink fixing layer, even if a large number of films are stacked and stored in a high temperature or hot and humid environment for a long time, the blocking phenomenon in which the films stick together will not occur. In this way, the scratch resistance and heat and humidity resistance are also significantly improved.

〔Example〕

Next, examples of the present invention will be described.

Example 1 (Sumikaflex 900, solid content 50%, Sumitomo Chemical Dermatology 1 colloidal silica 20
Part (Cataroid 5I-40, solid M 1%,
A water-based paint consisting of 20 parts was applied to a transparent polyester film (thickness 100 μm
) using an applicator (1 mil) and dried for 5 minutes in a dryer at 60°C.

An ink fixing layer having a thickness of 3 μm was formed on the obtained film.

This film was printed using an RI tester.

General ink was used as the ink, and the volume was 0.25 cc.

When the ink setting time of this product was measured, it was 5 minutes.

Example 2 (Vinibran 270, solid + 1%, 20 parts of colloidal silica from Nissin Chemical Co., Ltd.
A water-based paint consisting of 20 parts was applied to the same film in the same manner as in Example 1 and then dried.

An ink fixing layer having a thickness of 3 μm was formed on the obtained film.

This film was printed using an RI tester and the ink set time was measured, which was 5 minutes. Comparative Example The same unprocessed transparent polyester film as in the above example was printed using an RI tester.

When the ink setting time of this product was measured, it took 5 hours.

〔Effect of the invention〕

The present invention is as described above, and the transparent printing paper of the present invention includes:
In addition to having good ink setting properties, ink drying properties, and ink adhesion properties for various types of printing, it also has general properties such as heat blocking properties, moist heat blocking properties, scratch resistance, stain resistance, and slip properties without compromising transparency. Its physical properties are also significantly improved compared to conventional products, and it is therefore suitable for various cards, labels, and films for overhead projectors. Furthermore, if a moldable base film is used, it can be used as various packaging materials after printing.

Claims (1)

[Claims] A coating liquid containing an emulsion of vinyl acetate-ethylene-acrylic copolymer resin or/and vinyl chloride-acrylic copolymer resin as a main component is applied to at least one side of a substrate made of a transparent plastic film to form an ink fixing layer. A transparent printing paper characterized by comprising: