JPS6092849A - Transparent film for aqueous ink recording - 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 The present invention relates to a transparent film for inkjet recording suitable for inkjet recording.

Inkjet recording is a method in which recording liquid called ink is ejected from minute nozzles to adhere to a recording material and perform recording. Since the ink of the recording medium is a liquid, clogging due to drying of the ink inside the micro nozzles is a problem, and a countermeasure has been taken to suppress drying by adding a low vapor pressure solvent to a part of the ink composition. There is.

In general, Oh, (--Head @ Groziekta (hereinafter referred to as 0F
Films made of polyester, polyethylene, etc. are used for transparent films (referred to as IP) because they have high transparency, heat resistance, and do not warp due to differences in environmental conditions, depending on the purpose of use. The current situation is that These films have completely different properties from paper; they are neither hydrophilic nor have a porous structure, so they can be used as a recording medium by recording with a highly volatile pen, but the recording medium dries quickly on the film. We use materials that will stick.

On the other hand, as mentioned above, Inkciendo recording ink is
Since it contains a low vapor pressure solvent to prevent drying inside the micro nozzle, it does not dry at all on the current 0FIP film, making it impossible to print using the inkjet recording method.

An object of the present invention is to provide a transparent film for inkjet recording that solves these drawbacks and provides good recording even in an inkjet recording system.

The present invention satisfactorily satisfies these objectives by providing an entire substrate of a transparent glass film that is not soluble in water and has excellent environmental resistance, and providing a transparent layer containing a water-absorbing gold on at least one surface of the substrate. Since it absorbs ink-end ink immediately after it is applied and has quick-drying properties, it enables good recording even in ink-end recording.

To explain the present invention in more detail, examples of the plastic film as a transparent substrate having excellent environmental resistance include polyester, polypropylene, polyester, polyvinyl chloride, polystyrene, polycarbonate, and moisture-proof hexafluorocarbons. The thickness of the film varies from 30 μm to 500 μm, depending on the relative thickness with the transparent layer containing the water-absorbing gold.
It may be within the μm range. Considering all factors such as operability with a printer, a range of 50 μm to 200 μm is preferable.

The water-absorbing transparent layer may be a coating layer of a water-soluble polymer or a water-insoluble polymer compound containing water-absorbing gold. To explain in more detail, the water-soluble polymer layer absorbs ink when it comes into contact with the film. It can be obtained by laminating a water-soluble polymer film. Specifically, the thickness of polyvinyl alcohol, gelatin, and carboxymethyl as a whole is appropriately determined by fully considering environmental resistance such as humidity and temperature, and may be in the range of 6 μm to 100 μm. Considering everything including ink absorption capacity, it is 10μm.
A suitable range is from 50 μm to 50 μm.

In the same way as water-soluble polymer films, ink can be quickly prepared using copolymers, sodium acrylate polymers, sodium acrylate, acrylamide copolymers, saponified vinyl acetate/methyl acrylate copolymers, and the like. These have a water absorption capacity of 10 to SOO times their own volume, and even in ink containing a wetting agent, they have an absorption capacity of about 100 times. Examples of the binder that binds all of these superabsorbent polymer compounds include casein, polyvinyl alcohol, carboxymethyl cellulose, methyl cellulose, poly(7-IJ) sodium phosphate, polyvinyl chloride, polystyrene, and oligomethacrylate. When the amount of the binder-j is about 50.05 parts by weight to 1 part by weight of the superabsorbent polymer compound, favorable results can be obtained. The coating amount is preferably in the range of 5 f/d to 20 f/d to 20 f/d in terms of solid content in view of quick drying and climbing properties as a film.

Furthermore, an antifungal agent or the like may be added to the water-soluble polymer film layer and the superabsorbent polymer compound coating layer, if necessary.

Furthermore, if the water-insoluble film used as the substrate has excellent environmental resistance, and if it causes problems in adhesion with the above-mentioned ink-absorbing layer, it can be surface-treated as necessary to give it polar groups. It is also possible to bind a water-soluble polymer film layer or a superabsorbent polymer compound.

As described above, by using the transparent film for inkjet recording obtained according to the present invention, it has become possible to realize quick-drying and high-quality recording using an inkjet recording method.

Hereinafter, the present invention will be explained in more detail by showing examples.

Example 1 35 μm ft of cold water-soluble polyvinyl alcohol film was applied to a 100 μm transparent film of polyester as a base material.
Laminate to obtain the film gold of the present invention.

The obtained film has high transparency and can withstand high temperature and humidity conditions (
80℃. The film was in good condition, with no warping or expansion/contraction observed even under the conditions of 90 inches.

Furthermore, using this film, recording was performed using an ink whose main components were a hydroxyl dye, a wetting agent, and water. After printing, it dried in 5 osec to 60 sec, and a record 1 with a good dot diameter was obtained. I was able to do that. Furthermore, the static electricity between the films was also good, and a film free from dust was obtained. In addition, by using a polyvinyl alcohol film with minute irregularities on its surface, the transparency is slightly reduced, but the front and back sides of the film can be easily distinguished, and the films do not stick together even under high temperature and humidity. Ta.

Although the printed surface of the transparent film has sufficient environmental resistance for general use, it is expected that it may come into contact with water unexpectedly during use. Therefore, for items that are important for the purpose of use, it was possible to sufficiently retain the entire printed film by sealing the entire printing surface with a film that has excellent environmental resistance similar to the substrate.

Also, if the pH value of the ink mentioned above is 120 or more,
It absorbs more effectively and dries faster than polyvinyl alcohol film. It is now possible to perform ink-end recording with even better weather resistance.

Example 2 After applying UV treatment to one side of a 120 μm film of polyethylene as a base material to impart polarity, a water-absorbing polymer layer composition having the composition shown below was mixed and ground in a ball mill for 10 hours. Coat with a coating of 7f/ln'' and dry.

Water absorbency 1 Molecular layer composition wt% 0 Sodium acrylate polymer (2 μm (7%) 20.0
0 Polyvinyl alcohol 2.0 0 Water 780 The obtained film has good transparency and can withstand high temperature and humidity conditions (
The film was in good condition with no expansion or contraction observed even at temperatures of 80° C. and 90%. Furthermore, when inkjet recording was performed in the same manner as in Example 1, the recording time after printing was 3 osec to 6 osec.
It was possible to obtain good records without bleeding by drying with GSeC.

Comparative Example 1 When inkjet recording was carried out in the same manner as in Example 1 using a polyethylene film conventionally used as an OHPH film, it did not dry at all and did not fix even after being left for several hours.

Comparative Example 2 When printing was carried out using a 50 μm film of water-soluble polyvinyl alcohol, the drying time was 5ase.
c~60SeC, which is almost the same as the Example, good results were obtained, but the film expanded and contracted in a high temperature atmosphere and was not practical.

As explained above using Examples and Comparative Examples, the film obtained by the present invention has a water-absorbing transparent layer that quickly absorbs and fixes attached ink, and is able to absorb and fix adhering ink better than conventional films. We were able to make complete recording possible using the inkjet recording method, which was previously impossible. As a film, it has excellent transparency, is unaffected by environmental conditions such as humidity and temperature, has effects such as controlling static electricity, which has been a problem in the past, and has a good film quality with no buildup. It was something.

All of the above explanations are based on the inkjet recording method as a specific example, but water-based ballpoint pens using water-based ink,
It is also sufficiently effective for recording using felt-tip pens or other instruments.

Claims (1)

[Claims] A transparent film for water-based ink recording, characterized in that a water-absorbing transparent layer is provided on at least one surface of a water-insoluble transparent plastic film.