JPH07149089A - File for saving inkjet recording sheet - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a file for storing an inkjet recording sheet, which has good storability and transparency of an inkjet recording image. [Structure] A film having a haze value of 10% or less specified by ASTM D1003 is used as a base material, and an antioxidant of 1 mg / m is provided on the surface of the base material in contact with an inkjet recording sheet.
Inkjet recording sheet storage file with a coating layer containing ^two or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file for storing an ink jet recording sheet after printing, and more specifically, a file for storing an ink jet recording sheet excellent in storability and transparency of an ink jet recording image. It is about.

[0002]

2. Description of the Related Art Ink jet recording is a system in which minute droplets of ink are ejected by various operating principles and adhered to a recording sheet such as paper or film to record images, characters and the like. Inkjet printers have features such as high-speed printing, low noise, high flexibility in recording patterns, and no need for development or fixing, and can form complex images accurately and quickly. In recent years, it has been rapidly popularized for various purposes, especially as a hard copy creating apparatus for image information such as characters and various figures created by a computer.

In the ink jet recording system, it is easy to perform multicolor recording by using a plurality of ink nozzles. The multi-color inkjet recording method is widely used because it is possible to obtain images that are comparable to multi-color printed matter and color photographs, and it is cheaper than printing technology and photographic technology for applications with a small number of copies. It's starting.

In recent years, the fields of use of ink jet printers, which have received a great deal of attention, include the production of color proofs and the output of design images in the design field in the printing field where high image quality close to that of photographs is required. Further, it is also practiced to output characters and image information created by a computer to a transparent recording sheet using an inkjet printer, and use this as an original for an overhead projector for presentations at conferences and the like.

In general, a recording sheet used in such an ink jet recording system has an ink receiving medium composed of a water-soluble resin, an inorganic pigment, an additive, etc. on a support such as paper or film in order to improve ink absorbability. It is produced by providing layers. Then, an ink containing a dye, a pigment, water, a water-soluble organic solvent and the like is attached to a recording sheet using an inkjet printer to form an image.

By the way, it is known that when an image printed by the ink jet recording system is stored for a long period of time, the image is discolored due to oxidative decomposition of dyes and pigments in the ink. For this reason, an ink containing a dye or pigment having high fastness is used, or the ink described in JP-A-55-151041 and JP-A-55-151041.
As described in JP-A-5-164976, JP-A-58-180549, JP-A-60-5394, etc.,
Attempts have been made to improve the storability of images by adding an antioxidant to the ink receiving layer of the inkjet image receiving sheet.

However, the fastness of dyes and pigments that can be used in the ink jet recording system is limited, and when an antioxidant is added to the ink receiving layer of an ink jet image receiving sheet, the antioxidant decomposes in the ink receiving layer. There was also a problem of coloring.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a file for storing an ink jet recording sheet, which has good storability and transparency of an ink jet recorded image which cannot be realized by such a conventional technique.

[0009]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that a film having a low haze value is used as a base material in a file for storing an ink jet recording sheet. By using a coating layer containing a specific amount of an antioxidant on the surface of the base material that is in contact with the ink jet recording sheet, it is possible to prevent discoloration of the ink jet recording image due to oxidative decomposition of dyes and pigments, and an ink receiving layer. It was found that an ink jet recording sheet storage file having good storage stability and transparency can be obtained because coloring due to decomposition of the antioxidant therein can be prevented, and the present invention has been completed.

That is, the inkjet recording sheet storage file of the present invention is an inkjet recording sheet storage file on which an image is formed by an inkjet printer, and the base material of the file is ASTM D1003.
And a coating layer containing an antioxidant of 1 mg / m ² or more is provided on the contact surface with the recording sheet.

The ink jet recording sheet storage file of the present invention will be described in detail below.

In the present invention, the base material of the file for storing the ink jet recording sheet is ASTM D100.
A film having a haze value defined by 3 of 10% or less is preferable. When the haze value of the film exceeds 10%,
Since the transparency of the file is lowered, it is difficult to observe the image in detail when the inkjet recording sheet is stored in the file.

Examples of such a film include polyethylene film, polypropylene film, polyester film, polyamide film, polyvinyl chloride film,
Polyvinylidene chloride film, polystyrene film,
Polycarbonate film, polysulfone film,
An acetate film or the like can be used. In addition, the thickness of the film is 2 from the viewpoint of handleability and cost.
About 0 to 100 μm is suitable.

The antioxidant to be added to the coating layer provided on the surface of the substrate that contacts the ink jet recording sheet is
For example, 2,6-di-t-butyl-4-methylphenol, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-). Butylphenol), 4,4'-thiobis (3-methyl-6-t-butylphenol), 2,
2'-thiobis (4-methyl-6-t-butylphenol), 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl)
Benzene, phenol compounds such as 1,3,5-tris (2-methyl-4-hydroxy-5-t-butylphenol) butane, sulfide compounds such as dilaurylthiodipropionate and distearylthiodipropionate, Phosphite compounds such as tridecyl phosphite, diphenyldecyl phosphite, triphenyl phosphite, and trisnonyl phenyl phosphite,
Examples thereof include thiourea compounds such as thiourea and ethylthiourea, methanesulfonic acid compounds such as hydroxymethanesulfonic acid and aminomethanesulfonic acid, aromatic amine compounds, and acid amide compounds.

The amount of the antioxidant added to the coating layer provided on the surface of the substrate which contacts the ink jet recording sheet is preferably 1 mg / m ² or more. Addition amount is 1
If the amount is less than mg / m ² , the antioxidant effect is lowered and the discoloration of the inkjet recorded image cannot be suppressed.

In the present invention, the coating layer provided on the surface of the base material in contact with the ink jet recording sheet contains the above-mentioned antioxidant together with a binder, an antistatic agent, a cross-linking agent, a plasticizer, a surfactant and the like in an organic solvent or It is dissolved or dispersed in water and coated on a substrate.

As the binder, for example, organic solvent-soluble resins such as polyurethane, polyester, polyvinyl chloride, polyamide, polyether, polycarbonate, etc.,
Water-soluble resins such as polyvinyl alcohol, starch, gelatin and casein, resin emulsions such as polyacrylic acid ester type resin emulsions, polyvinyl acetate type resin emulsions, styrene / acrylic type resin emulsions and styrene / butadiene resin emulsions can be used.

As the antistatic agent, inorganic salts such as sodium chloride and potassium chloride, organic antistatic agents such as polyethylene glycol type, polystyrene sulfonic acid type, polyacrylic acid ester type and the like, and as the cross-linking agent, melamine / Formalin resin, urea resin, polyamide resin, polyethyleneimine resin, epoxy resin, etc., plasticizers such as phthalic acid ester, trimellitic acid ester, pyromellitic acid ester, etc., and surfactants such as anionic surfactant, cation. A cationic surfactant, an amphoteric surfactant, a nonionic surfactant and the like can be used.

The coating layer containing such an antioxidant is generally used in gravure method, reverse roll method, wire bar method, extrusion die method, comma method, curtain method, air knife method, slide hopper method, etc. The base material can be applied by a coating method.

In the present invention, for the purpose of preventing blocking between ink jet recording sheet storage files, improving the light resistance of the image of the ink jet recording sheet, and the like, the surface of the substrate which is not in contact with the ink jet recording sheet is A coating layer may be provided in order to impart conductivity, releasability, ultraviolet absorptivity, etc. within a range that does not impair the effects of the present invention.

In such a coating layer, a pigment, a binder, a dispersant, an ultraviolet absorber, a surfactant, an antistatic agent, a cross-linking agent, a plasticizer, a pH adjuster, a thickener and the like are added to water or an organic solvent. Can be dispersed and applied to a substrate by general coating methods such as gravure method, reverse roll method, wire bar method, extrusion die method, comma method, curtain method, air knife method, slide hopper method, etc. .

[0022]

In the present invention, when a film having a low haze value is used as the base material and a coating layer containing an antioxidant is provided on the surface of the base material that is in contact with the ink jet recording sheet, the effect of the antioxidant is exerted on the surface of the file. In addition to being able to prevent discoloration due to oxidative decomposition of the stored ink jet recorded image, by providing a space between the ink receiving layer and the antioxidant, decomposition of the antioxidant by the components of the ink receiving layer is suppressed, Since the coloring of the ink jet recording sheet can be prevented, a file for storing the ink jet recording sheet having good storability and transparency of the ink jet recorded image can be obtained.

[0023]

The present invention will be described in more detail by way of examples, but the contents of the present invention are not limited to these.

Example 1 A polyethylene terephthalate film having a haze value of 1.8% and a thickness of 50 μm was coated on one side with a gravure coater to prepare a coating solution having the following composition and a dry coating amount of 0.45 g /
It was coated and dried so as to be m ² . Then, the surface provided with the coating layer of this film was folded in two, and two of the three sides were glued to prepare an inkjet recording sheet storage file. (Coating layer coating liquid formulation 1) Polyacrylic acid ester resin 97.9 parts by weight 2,6-di-t-butyl-4-methylphenol 1 part by weight Polyethylene glycol antistatic agent 1 part by weight Silicone resin beads 0.1. 1 part by weight Toluene 150 parts by weight Methyl ethyl ketone 150 parts by weight

Example 2 In Example 1, the substrate was made to have a haze value of 3.9% and a thickness of 50.
An inkjet recording sheet storage file was prepared in exactly the same manner as in Example 1 except that the polypropylene film was changed to a μm polypropylene film.

Example 3 In Example 1, the substrate was made to have a haze value of 9.6% and a thickness of 50.
Example 1 except that the polyethylene film was changed to μm.
A file for storing an inkjet recording sheet was prepared in exactly the same manner as in.

Example 4 An ink jet recording sheet storage file was prepared in the same manner as in Example 1 except that the coating liquid for the coating layer was changed to the following composition. (Coating layer coating liquid formulation 2) Poly vinyl chloride resin 80 parts by weight Dioctyl phthalate 15 parts by weight Tridecyl phosphite 5 parts by weight Toluene 150 parts by weight Methyl ethyl ketone 150 parts by weight

Example 5 An ink jet recording sheet storage file was prepared in the same manner as in Example 1 except that the coating liquid for the coating layer was changed to the following composition. (Coating layer coating liquid formulation 3) Polyester resin 85 parts by weight 2,2'-methylene bis (4-methyl-6-t-butylphenol) 15 parts by weight Toluene 150 parts by weight Methyl ethyl ketone 150 parts by weight

Example 6 An ink jet recording sheet storage file was prepared in the same manner as in Example 1 except that the coating liquid for the coating layer was changed to the following formulation. (Coating layer coating composition 4) Poly vinyl acetate resin emulsion 98.9 parts by weight Human hydroxymethane sulfonic acid 1 part by weight Polystyrene resin beads 0.1 part by weight

Example 7 In Example 1, the dry coating amount of the coating liquid for the coating layer was 0.12.
An inkjet recording sheet storage file was prepared in the same manner as in Example 1 except that the file was set to g / m ² .

Comparative Example 1 A polyethylene terephthalate film having a haze value of 1.8% and a thickness of 50 μm was folded in two, and two of the three sides were glued to prepare a file for storing an ink jet recording sheet.

Comparative Example 2 A semitransparent polyvinyl chloride film having a haze value of 30.2% and a thickness of 50 μm and having irregularities on the surface is folded into two, and 3
Two of the sides were glued to prepare an inkjet recording sheet storage file.

COMPARATIVE EXAMPLE 3 In Example 1, the substrate was made to have a haze value of 12.5% and a thickness of 5
An inkjet recording sheet storage file was prepared in the same manner as in Example 1 except that the polyethylene film was changed to 0 μm.

Comparative Example 4 An ink jet recording sheet storage file was prepared in the same manner as in Example 1 except that the coating layer coating liquid was changed to the following composition. (Coating layer coating solution formulation 5) Polyacrylic acid ester resin 98.8 parts by weight 2,6-di-t-butyl-4-methylphenol 0.1 part by weight Polyethylene glycol antistatic agent 1 part by weight Silicone resin beads 0.1 parts by weight Toluene 150 parts by weight Methyl ethyl ketone 150 parts by weight

Comparative Example 5 In Example 1, the coating amount of the coating liquid for the coating layer was 0.08.
An inkjet recording sheet storage file was prepared in the same manner as in Example 1 except that the file was set to g / m ² .

In order to evaluate the performance of the ink jet recording sheet storage file prepared as described above, a 100 μm thick polyethylene terephthalate film was coated on both sides with an ink receiving layer coating solution having the following composition in a dry coating amount. An inkjet recording sheet coated and dried to have a weight of 5 g / m ² was used. (Ink receiving layer coating liquid formulation) Carboxymethyl cellulose 100 parts by weight Silica 20 parts by weight Colloidal silica 10 parts by weight Sulfosuccinic acid octyl ester 1 part by weight Water 869 parts by weight

The performance of the ink jet recording sheet storage file was evaluated by the following method.

(Discoloration of Inkjet Recorded Image) An inkjet recording sheet printed using a Hewlett Packard desk writer 550C inkjet printer was put in an inkjet recording sheet storage file and stored for 1 month at 20 ° C. and 65% RH. After that, the state of discoloration in the black portion of the ink jet recorded image was visually observed, and the one in which almost no discoloration was observed was rated as O, the one in which a slight discoloration was recognized was rated as Δ, and the one in which the discoloration was remarkable was rated as X.

(Coloring of Inkjet Recording Sheet) An inkjet recording sheet printed by using a Hewlett Packard desk writer 550C inkjet printer is put in an inkjet recording sheet storage file and stored for 2 weeks at 30 ° C. and 80% RH. ,
The coloring state in the non-image area of the ink jet recording sheet was visually observed. When little coloration was observed, it was evaluated as ◯, when a little coloration was recognized as Δ, and when it was markedly colored as x.

(Transparency) An inkjet recording sheet printed by using a Hewlett Packard desk writer 550C inkjet printer was put in a file for storing the inkjet recording sheet, and the image on the inkjet recording sheet was visually observed, and the file was free from fogging. When the image could be observed in detail, it was evaluated as ◯, and when it was slightly clouded and it was a little difficult to observe the detailed image, it was evaluated as Δ, and when it was too cloudy to observe the detailed image and could not be used, it was evaluated as x.

The results of the above evaluations are summarized in Table 1.

[0042]

[Table 1]

As is clear from Table 1, the ink jet recording sheet storage files of Examples 1 to 7 had good transparency and neither discoloration of the ink jet recording image nor coloring of the ink jet recording sheet. However, in the inkjet recording sheet storage file of Comparative Example 1, the inkjet recording image was discolored because the coating layer containing the antioxidant was not provided. The ink jet recording sheet storage file of Comparative Example 2 uses a semi-transparent polyvinyl chloride film having irregularities on the surface as a base material and does not have a coating layer containing an antioxidant, and thus has low transparency. The inkjet recorded image is discolored. Since the inkjet recording sheet storage file of Comparative Example 3 uses a polyethylene film having a high haze value as a base material, its transparency is lowered, and it is difficult to observe an image in detail when the inkjet recording sheet is put in the file. It was Comparative Example 4
In the ink jet recording sheet storage files Nos. 5 to 5, the ink jet recording image was discolored because the amount of the antioxidant contained in the coating layer was too small.

[0044]

According to the present invention, a film having a low haze value is used as a base material, and a coating layer containing a specific amount of an antioxidant is provided on the surface of the base material in contact with the ink jet recording sheet. Thus, a file for storing an inkjet recording sheet, which has good storability and transparency of the inkjet recording image, can be obtained.

Claims (1)

[Claims] 1. A file for storing an inkjet recording sheet on which an image is formed by an inkjet printer, wherein a base material of the file has a haze value of 10% or less defined by ASTM D1003, and a contact surface with the recording sheet. An inkjet recording sheet storage file, characterized in that a coating layer containing 1 mg / m ² or more of an antioxidant is provided.