JPH11198522A - Ink jet recording medium and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have a practically sufficient physical property of base material, and give a microbe decomposition property, and also obtain an ink jet recording characteristic by coating aliphatic polyester on at least one surface of paper base material in a carrier, and providing an ink receptor layer on the carrier. SOLUTION: As a carrier, e.g. polybutylene succinate is applied having a thickness of about 10 μm on both the surfaces of code paper by an extruder under melt heat. Following this, a composition consisting of 100 pts.wt. polyvinyl alcohol of a saponification degree of about 91% as an image receptor layer, 5 pts.wt. ethylene glycol diglycidyl ether, 2 pts.wt. a 2-methyl imidazole solution of 10% as a curable medium, and 15 pts.wt. rice starch is blended in a water- isopropanol solution and applied on one surface of the carrier by wire bar coating with a thickness of about 15 μm. After coating, it is heated in an oven of 120 deg.C for about three minutes so as to form an ink jet recording body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium for an ink jet printer and a method for manufacturing the same, and more particularly to a recording medium which is degradable by microorganisms after disposal.

[0002]

2. Description of the Related Art In recent years, various types of printers have become widespread for computer output and the like. Above all, an ink jet printer is excellent in quietness, cost, and image quality, can reproduce a full-color image with high quality, has excellent performance not found in other systems, and can be expected to spread further. On the other hand, paper is frequently used for printer paper, and plastic films and synthetic paper are also used for applications requiring smooth images utilizing the smooth surface thereof and transparency such as OHP.

Further, in order to prevent clogging of an ink nozzle, an ink which dissolves a water-soluble dye or the like in an aqueous solvent and is slowly dried is used as an ink-jet ink. Therefore, if the recording paper is water-absorbing such as paper, it is good, but if it is non-water-absorbing such as a plastic film, the ink has poor drying properties after printing. Provide an ink image receiving layer having a property.

On the other hand, with the spread of word processors, personal computers, and the like, the amount of discarded information recording paper has increased and has become a problem. In recent years, plastic products occupy a large part of the wastes which are problematic in environmental issues, and are regarded as materials which are extremely difficult to treat due to their properties which do not decompose semi-permanently. Ink-jet recording media especially used for high-grade applications use plastic-based or paper-based resin-coated substrates, so when they are landfilled and disposed of, they must exist for many years, just like ordinary plastics. Was a problem.

Hitherto, there has been a problem that information recording papers other than papers, such as high-quality ink jet recording media, have properties equivalent to those of general plastics without taking into consideration the effect on the environment after disposal. .

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and uses a base material mainly composed of an aliphatic polyester having biodegradability and is practically used as a product. Has sufficient substrate properties, and the image receiving layer also has microbial degradability, and has excellent inkjet recording characteristics, which can contribute to solving the problem of waste of high-quality information recording media, which continues to increase. An object of the present invention is to provide a possible ink jet recording medium and a method for manufacturing the same.

[0007]

Means for Solving the Problems The present invention has been made to achieve the above object, and the invention according to claim 1 is characterized in that the support comprises a paper substrate and an aliphatic polyester on at least one surface of a paper substrate. An ink jet recording medium which is coated and has an ink image receiving layer provided on the support. When an ink image receiving layer is provided directly on a paper substrate, the paper is not water-resistant, so when printing with a large amount of ink, such as printing an image, or when storing under high humidity, the original substrate is smooth. May not be able to maintain sex. However, in the support of the present invention, by coating the base material with a resin, the base material itself is made to have water resistance even with paper,
The reliability of the recording medium can be improved.

A second aspect of the present invention is based on the ink jet recording medium according to the first aspect, wherein the aliphatic polyester is preferably polylactic acid, polycaprolactone, polyhydroxybutyrate, polyhydroxyvalerate or At least one of the polyalkylene alkylates is used alone or in the form of a copolymer. The above-mentioned resin is not only a material that is suitable for the environment having microbial decomposability but also has thermal decomposability, and can be easily hot-melt coated on paper using various extruders and the like.

According to a third aspect of the present invention, there is provided an ink jet recording medium comprising a support made of a polylactic acid film and an ink image receiving layer formed on the support. By using a polylactic acid film as a base material, an all-plastic recording medium having excellent smoothness can be provided. Furthermore, since polylactic acid is colorless and transparent, OH
It can also be suitably used for applications requiring transparency, such as P sheets.

[0010] The invention described in claim 4 is the first to third aspects of the present invention.
The basic structure of the ink jet recording medium according to any one of the above, wherein the ink image receiving layer contains polyvinyl alcohol. Conventionally, various resins have been used for the ink image receiving layer, but most of them have no microbial degradability. Polyvinyl alcohol (PVA) is not only biodegradable but also excellent in ink jet recording characteristics.

[0011] The invention according to claim 5 provides the invention according to claims 1 to 4.
Wherein the ink image-receiving layer contains an aliphatic polyfunctional epoxide. Polyvinyl alcohol (PVA) has excellent ink jet recording properties, but has almost no water resistance because it is water-soluble. But,
In the present invention, for the purpose of improving water resistance, an aliphatic polyfunctional epoxide having the least adverse effect on microbial degradability is added to the image receiving layer and thermally cured, thereby achieving both water resistance and microbial degradability. Can be done.

[0012] The invention according to claim 6 is the invention according to claims 1 to 5.
Wherein the ink image receiving layer contains inorganic and resin fine particles as a filler. It is more desirable to add a filler in order to improve the ink absorbency and recording characteristics. By adding a filler, it is possible to reduce so-called beading “ink bleeding”.

According to a seventh aspect of the present invention, there is provided the ink jet recording medium according to the sixth aspect of the present invention, wherein the filler comprises starch-based fine particles. Since starch-based fine particles are a natural material, they have good microbial degradability and extremely excellent printing characteristics.

The invention according to claim 8 is a method for manufacturing an ink jet recording medium, wherein a paper base material coated with an aliphatic polyester on at least one side is used as a support and an ink image receiving layer is provided on the support. Is the way.
When an ink image receiving layer is provided directly on a paper substrate, the paper is not water-resistant, so when printing with a large amount of ink, such as printing an image, or when storing under high humidity, the original substrate is smooth. May not be able to maintain sex. However, in the support of the present invention, by coating the base material with a resin, the base material itself is made to have water resistance even with paper, and the reliability of the recording medium can be improved.

The invention according to claim 9, wherein a polylactic acid film is used as a support, and an ink image-receiving layer is provided on the support.
By using a polylactic acid film as a base material, an all-plastic recording medium having excellent smoothness can be provided. Furthermore, since polylactic acid is colorless and transparent, it can be suitably used for applications requiring transparency, such as OHP sheets.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The ink jet recording medium of the present invention, in order to solve the above-mentioned problems and achieve the object, a substrate coated with an aliphatic polyester on one or both sides on a paper substrate as a support, or a polylactic acid film as a substrate This provides a recording medium having a small environmental load after being disposed of and decomposed by microorganisms in the natural world in the soil.

The aliphatic polyester described in the present invention may be any biodegradable resin that can be coated on a paper substrate.
For example, polyethylene succinate, polybutylene succinate, polybutylene adipate, polyethylene adipate, polypropylene succinate, polypropylene adipate, polypropylene pimerate, polypropylene suberate, polypropylene azelate, polypropylene malonate, polypropylene diethyl glutarate, polyethylene pime Rate, polyethylene suberate, polyethylene azelate, polyethylene malonate, polyethylene diethyl glutarate, polybutylene pimerate, polybutylene belate, polybutylene azelate, polybutylene malonate, polybutylene diethyl glutarate, polyhexamethylene succinate Nate,
Polyhexamethylene adipate, polyhexamethylene pimerate, polyhexamethylene suberate, polyhexamethylene azelate, polyhexamethylene malonate,
Polyhexamethylene diethyl glutarate, polydiethylene succinate, polydiethylene adipate, polydiethylene pimerate, polydiethylene suberate, polydiethylene azelate, polydiethylene malonate, polydiethylene diethyl glutarate, polytriethylene succinate, poly Triethylene adipate, polytriethylene pimerate, polytriethylene suberate, polytriethylene azelate, polytriethylene malonate, polytriethylene diethyl glutarate, polyhydroxybutyrate, polyhydroxyvalerate, polycaprolactone, or And polylactic acid. Further, these copolymerized polyesters may be used.

As the paper substrate described in the present invention, various papers such as synthetic paper, high quality paper, art paper, coated paper, cast coated paper, paperboard and the like can be used.

The term "polylactic acid" as used in the present invention refers to a film formed by ring-opening polymerization via lactide of a cyclic dimer of lactic acid, or a sheet formed by directly polymerizing lactic acid. Etc. can be used. Those which have been subjected to a stretching process to improve the thermal stability as necessary are more preferable. These polylactic acid films are known to be decomposed and assimilated by natural microorganisms, and can be used as a base material of a recording medium having a low environmental load.

Since the ink image receiving layer provided on the ink jet recording medium has a thickness of usually about 20 to 40 μm, the use of an image receiving layer generally used for ink jets enhances environmental compatibility in the present invention. Therefore, the ink image receiving layer is also provided with microbial degradability.

In other words, the present inventors have developed a material which has not only the dyeability and wettability of the ink which can absorb the ink-jet ink but also the decomposability by microorganisms.
It has been found that an ink image-receiving layer having good recording properties and a microbial degradability can be obtained with a configuration containing polyvinyl alcohol as a main component, and the present invention has been completed by combining with the above-mentioned microbial degradable support. Was.

The polyvinyl alcohol is usually obtained by saponifying polyvinyl acetate in the presence of an alkali. As a result of intensive studies conducted by the present inventors, polyvinyl alcohol obtained by saponifying polyvinyl acetate with a saponification degree of 90% or more exhibits particularly excellent performance in terms of degradability by microorganisms. Those are particularly preferred in the present invention. It is known that the biodegradability is generally better as the amount of the vinyl alcohol component is larger, that is, as the degree of saponification is higher. However, according to the present inventors, it has been confirmed that if the saponification degree is less than 90%, the microbial degradability is significantly reduced, and for that reason, less than 90% is not so preferable. Although the polyvinyl alcohol is hydrophilic, but water-soluble, after inkjet recording,
Poor stability against moisture. In the present invention, an aliphatic polyfunctional epoxide is added, and the polyvinyl alcohol is heated and crosslinked to impart water resistance to the ink image receiving layer, thereby improving the properties.

The aliphatic polyfunctional epoxide described in the present invention includes, for example, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, resorcinol diglycidyl. Ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, or an aliphatic system such as polypropylene glycol diglycidyl ether, and those that are water-soluble epoxy compounds, after curing Particularly good in properties and biodegradability.

These aliphatic polyfunctional epoxides are preferably added at a ratio of not more than 20% to the solid content of the resin,
It is desirable to form the image receiving layer by heating and curing in an oven or the like. The higher the ratio, the higher the water resistance, but if it exceeds 20%, the biodegradability decreases.

For the purpose of improving the recording characteristics of the ink image receiving layer, a cation-modified acrylic copolymer or a polyvinyl acetal resin may be added as necessary.

In the present invention, an inorganic or organic filler is added for the purpose of improving the water absorbing property of the ink. These fillers are usually contained in the ink image receiving layer in an amount of about 5 to 50 wt%,
Preferably, about 0.1 to 20 wt% is contained. If the addition ratio is too small, sufficient transportability and blocking resistance cannot be obtained. In the case of a transparent image such as OHP, if the amount is too large, the transparency is impaired.

Examples of the inorganic or organic filler described in the present invention include, for example, inorganic particles such as silica, clay, calcium carbonate, barium sulfate, alumina white, aluminum hydroxide, talc, bentonite, and titanium oxide. The fine particles are composed of a thermosetting resin such as polymethyl methacrylate, polystyrene, a fluororesin vinyl resin, a polyolefin resin such as polyethylene and polypropylene, a thermoplastic resin such as polyamide, a polybenzoguanamine resin, or a urea resin. Fine particles having an average particle diameter of 30 μm or less, particularly 0.1 to 20 μm, are excellent.

As long as the inorganic filler among the above fillers exists in the natural world, there is no problem with respect to the environment.
Many organic fillers have poor microbial degradability and tend to burden the environment. In the present invention, it has been found that the starch-based fine particles are excellent in the microbial degradability of the image receiving layer in consideration of the filler and the microbial degradability. The starch-based fine particles described in the present invention include rice starch, corn starch, potato starch and the like.

The materials for the ink image receiving layer as described above may be any one or a mixture of two or more of water, methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, toluene and xylene. Is used as a coating liquid of a 10 to 50% by weight solution. Also, in the ink image receiving layer,
Depending on the purpose, other resins other than those mentioned above, or a surfactant, an ultraviolet absorber, an antioxidant, a pH adjuster, a defoaming agent and other additives may be appropriately mixed within a range not departing from the performance. .

The thickness of the ink image receiving layer is usually from 1 to 50 μm.
m, preferably about 3 to 20 μm. If the thickness is too small, the dyeing properties will be insufficient, and the drying property and the anti-blocking property will be reduced. Conversely, if the thickness is too large, the cost will increase and the curl will increase. The ink image-receiving layer is formed by coating a coating solution obtained by mixing the above-described base agent and curing agent at an appropriate equivalent ratio on at least one surface of the support by a known coating method such as gravure coating, roll coating, or wire bar coating. I just need to work.

The aqueous ink that can be used in the ink jet recording medium of the present invention is a known ink jet ink, and is usually a water-soluble dye, a wetting agent, a dye solubilizing agent, a preservative, water, water miscibility. It consists of an organic solvent and the like.

<Function> As described above, in the ink jet recording medium of the present invention, a paper substrate or a polylactic acid film coated with an aliphatic polyester is used for the support, and the ink image-receiving layer is composed mainly of polyvinyl alcohol. By using such a structure, it is possible to provide a material having extremely low environmental load after disposal.

[0033]

<Example 1> As a support, a thickness of about 100 μm was used.
m on both sides of the coated paper, melted and heated polybutylene succinate (trade name: Bionore, manufactured by Showa High Polymer Co., Ltd.)
About 10 μm was applied by an extruder. On one side of the support, as an image receiving layer, a polyvinyl alcohol saponification degree of about 91% (trade name: PVA-706, manufactured by Kuraray Co., Ltd.)
100 parts by weight, 5 parts by weight of ethylene glycol diglycidyl ether, 2 parts by weight of a 10% aqueous solution of 2-methylimidazole as a curing catalyst, rice starch (trade name: Micropearl,
A composition consisting of 15 parts by weight of Nissei Chemical Co., Ltd.) was mixed with a water-isopropanol solution, and applied to a thickness of about 15 μm by wire bar coating. After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

<Example 2> A support having a thickness of about 100
Polycaprolactone (trade name) on both sides of μm coated paper
Plaxel H-7, manufactured by Daicel Chemical Industries, Ltd.) was applied with an extruder to about 10 μm under melting and heating.
On one side of the support, 100 parts by weight of polyvinyl alcohol saponification degree 93% (trade name: PVA-613, manufactured by Kuraray Co., Ltd.) and glycerol polyglycidyl ether (trade name: Dinacol EX-314, Nagase Chemical Co., Ltd.) 5 parts by weight, 10% as a curing catalyst 2
A composition consisting of 2 parts by weight of an aqueous solution of 1-methylimidazole and 15 parts by weight of rice starch (trade name: Micropearl, manufactured by Nissei Chemical) was mixed with a water-isopropanol solution, and applied to a thickness of about 15 μm by wire bar coating. . After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

<Example 3> A support having a thickness of about 100
Polyhydroxybutyrate (trade name; manufactured by Biopol, Monsanto) was applied to both sides of a coated paper having a thickness of 10 μm by an extruder under melting and heating. On this support, a polyvinyl alcohol saponification degree of about 93 was formed as an image receiving layer.
% (Trade name: PVA-706, manufactured by Kuraray Co., Ltd.), 5 parts by weight of ethylene glycol diglycidyl ether, 2 parts by weight of a 10% 2-methylimidazole aqueous solution as a curing catalyst, rice starch (trade name: Micropearl, A composition consisting of 15 parts by weight of Nissei Chemical Co., Ltd.) was mixed with a water-isopropanol solution, and applied to a thickness of about 15 μm by wire bar coating. After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

Example 4 A support having a thickness of about 100
A μm polylactic acid film (trade name; Ecologe, manufactured by Mitsubishi Plastics, Inc.) was used. On this support, a polyvinyl alcohol saponification degree of about 93% (product name PVA-
706, 100 parts by weight of Kuraray Co., Ltd.), 5 parts by weight of ethylene glycol diglycidyl ether, 2 parts by weight of a 10% 2-methylimidazole aqueous solution as a curing catalyst, rice starch (trade name: Micropearl, manufactured by Nisseki Chemical) 15 The composition consisting of parts by weight was mixed with a water-isopropanol solution and applied to a thickness of about 15 μm by wire bar coating. After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

<Example 5> A support having a thickness of about 100
A μm polylactic acid film (trade name; Ecologe, manufactured by Mitsubishi Plastics, Inc.) was used. On this support, a polyvinyl alcohol saponification degree of about 98% (product name PVA-
105, manufactured by Kuraray Co., Ltd.) 100 parts by weight, ethylene glycol diglycidyl ether 5 parts by weight, 10% 2-methylimidazole aqueous solution 2 parts by weight as a curing catalyst, rice starch (trade name: Micropearl, manufactured by Nisseki Chemical) 15 The composition consisting of parts by weight was mixed with a water-isopropanol solution and applied to a film thickness of about 15 μm by wire bar coating. After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

<Example 6> A support having a thickness of about 100
A μm polylactic acid film (trade name; Ecologe, manufactured by Mitsubishi Plastics, Inc.) was used. On this support, 100 parts by weight of a cation-modified acrylic copolymer resin (trade name: Jurimer, manufactured by Nippon Pure Chemical Co., Ltd.) as an image receiving layer, 5 parts by weight of ethylene glycol diglycidyl ether, and 1 part as a curing catalyst
A composition consisting of 2 parts by weight of a 0% 2-methylimidazole aqueous solution and 15 parts by weight of rice starch (trade name: Micropearl, manufactured by Nissen Chemical Co., Ltd.) was mixed with a water-isopropanol solution. Was applied. After the application, the ink was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

Comparative Example 1 A support having a thickness of about 100
A μm polyethylene terephthalate film was used. On this support, a cation-modified acrylic copolymer resin (trade name: Julimer, manufactured by Nippon Pure Chemical Industries, Ltd.) 10 as an image receiving layer
0 parts by weight, ethylene glycol diglycidyl ether 5
A composition consisting of 2 parts by weight of a 10% 2-methylimidazole aqueous solution as a curing catalyst, and 15 parts by weight of rice starch (trade name: Micropearl, manufactured by Nichiden Chemical) is mixed with a water-isopropanol solution, and wire bar coating is performed. By
It was applied to a film thickness of about 15 μm. After the application, the mixture was heated in an oven at 120 ° C. for about 3 minutes to obtain an ink jet recording medium.

The following items were evaluated for the ink jet recording medium obtained as described above. In addition, printing was performed using an ink jet printer (BJC-420J, manufactured by Canon Inc.), and a color recorded image was formed using four color inks of yellow, magenta, cyan, and black, and evaluated. Microbial degradability was evaluated by storing the ink jet recording medium in a commercial garbage compost for about 20 days. Table 1 summarizes the results of each evaluation.

Recording Quality Immediately after printing, the recorded portion of the recorded material was visually observed to evaluate the degree of color reproducibility. ◎: Very clear image formed. を: Necessary and sufficient image formed. Δ: Poor ink absorbency and poor image quality. ×: Ink leakage was observed and no printing was performed.

[0042] evaluate the decomposition of the microbial decomposition of garbage compost. A: Completely decomposed. Or only some paper remains,
The resin part was completely decomposed. ；: Almost decomposed, but some resin remained. Δ: There are considerable parts that have not been decomposed. ×: Not decomposed at all.

[0043]

[Table 1]

As is clear from the results shown in Table 1, the ink jet recording media obtained in Examples 1 to 6 of the present invention were all excellent in recording characteristics and microbial degradability. Further, those using a polylactic acid film as a support had excellent transparency, and thus had excellent suitability as an OHP sheet.

[0045]

As described above, according to the present invention, a substrate having a biodegradable aliphatic polyester as a main component is used, the substrate exhibits practically sufficient physical properties as a product, and the image receiving property is improved. The present invention also provides an inkjet recording medium and a method for producing the same, which also have a microbial decomposability and are excellent in inkjet recording characteristics, and can contribute to solving the problem of waste of an ever increasing high-quality information recording medium. I was able to do it.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Yuka Tada 1-5-1, Taito, Taito-ku, Tokyo Letterpress Printing Co., Ltd.

Claims (9)

[Claims] 1. An ink jet recording medium comprising: a support on which at least one surface of a paper base is coated with an aliphatic polyester; and an ink image-receiving layer provided on the support. 2. The aliphatic polyester according to claim 1, wherein at least one of polylactic acid, polycaprolactone, polyhydroxybutyrate, polyhydroxyvalerate and polyalkylene alkylate is used alone or copolymerized. The inkjet recording medium according to claim 1, wherein: 3. An ink jet recording medium comprising a support made of a polylactic acid film and an ink image receiving layer formed on the support. 4. The ink jet recording medium according to claim 1, wherein said ink image receiving layer contains polyvinyl alcohol. 5. The ink jet recording medium according to claim 1, wherein said ink image receiving layer contains an aliphatic polyfunctional epoxide. 6. The ink jet recording medium according to claim 1, wherein said ink image receiving layer contains inorganic and resin fine particles as a filler. 7. The ink jet recording medium according to claim 6, wherein the filler contains starch-based fine particles. 8. A method for producing an ink jet recording medium, comprising: using a paper substrate having at least one surface coated with an aliphatic polyester as a support, and providing an ink image receiving layer on the support. 9. A method for producing an ink jet recording medium, comprising using a polylactic acid film as a support and providing an ink image receiving layer on the support.