JP2011178044A - Inkjet recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording material made from a synthetic resin which is adopted as a bag, film or sheet, and excellent in inkjet recording characteristics. <P>SOLUTION: The inkjet recording material is made from polyethylene or polypropylene and is excellent in recording characteristics by an inkjet printer, wherein corona discharge processing is performed to a recording point of the material, an anchor layer consisting of a polyamide resin is formed in a part in which the corona discharge processing has been performed, and an ink receiving layer is formed on the anchor layer. A wetting index of the recording point of the material by the corona discharge processing is desirably 40 dynes or more. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ink jet recording material, and more particularly to a synthetic resin material that is employed in bags, films, and sheets and has excellent ink jet recording characteristics.

  Polyethylene (PE) has 1) small specific gravity, 2) chemically stable, water and chemical resistance, 3) toughness, flexibility, and low embrittlement at low temperature 4) workability It is widely used for miscellaneous plastic bags, plastic bags, garbage bags, and product packaging sheets. Polypropylene (PP) is 1) elastic, 2) excellent in moisture resistance and transparency, and is used in packaging bags for miscellaneous goods, clothing and dry food.

  Recently, inkjet printers have become popular in homes and stores, and it has become possible to easily perform color printing.

  By the way, when producing original designed plastic bags, plastic bags, garbage bags, packaging films, etc., PE and PP are mainly used for these materials. However, household inkjet printers that use water-based inks cannot directly print on materials such as PE and PP, and an ink-receiving layer is required. In terms of properties, it is limited to polyethylene terephthalate (PET) (Patent Document 1, Patent Document 2, Patent Document 3), PE and PP are difficult to process the ink receiving layer, and even if the ink receiving layer can be processed, as a printed matter It is difficult to print with an ink jet printer from the standpoint of standard friction fastness and water weather resistance.

  For this reason, there is only a method for printing PE or PP by gravure printing or silk printing. When full-color printing is to be performed, a large number of blocks are required, the printing cost is high, and it is difficult to adopt for printing a small lot.

  On the other hand, by containing magnesium aluminate metasilicate fine powder and a cationic polymer as solid components, the ink has excellent shielding properties, drying properties, color development properties, fixing properties, and water resistance for ink jet recording. There has been proposed a printing ink in which a receiving layer can be formed (Patent Document 4).

JP 2007-130780 A JP 2007-130776 A JP 2004-181859 A JP 2008-213345 A

  However, since the printing ink for forming the ink receiving layer described in Patent Document 4 uses fine magnesium powder as a solid component, yellowing may occur in a portion in contact with air.

  The printing ink described above is weak against water, and the material and the ink receiving layer are fixed when dried. However, once water is applied, a water film is formed between the material and the ink receiving layer, and the ink receiving layer. There was a problem that the layers peeled off.

  An object of the present invention is to provide an ink jet recording material made of PE or PP that improves ink jet recording characteristics.

  Therefore, the ink jet recording material according to the present invention is a polyethylene or polypropylene ink jet recording material having excellent recording characteristics by an ink jet printer, and corona discharge machining is performed on the recording portion of the material. An anchor layer made of a polyamide resin is formed in the processed portion, and an ink receiving layer is formed on the anchor layer.

  There are two types of inks for ink jet printers, dyes and pigments, both of which have different fixing properties to the ink receiving layer. Therefore, there is a need for an ink receiving layer that enables fixing of different fixing inks. Further, in the case of ink for an ink jet printer, it is generally finished at a level of pH 7-9. When the pH value of the ink receiving layer itself is different from that of the printer, the ink after landing tends to be acidic or alkaline, causing discoloration. When obtaining the photographic image quality, the whiteness or discoloration of the ink receiving layer itself is an important point as the performance of the ink receiving layer.

  The feature of the present invention is that the wetting index of the recording portion of the material is increased by corona discharge, and an anchor layer made of polyamide resin is formed thereon.

  As a result, the fixability of the ink receiving layer to PE or PP is improved, and original-designed plastic bags, plastic bags, garbage bags, packaging films, and the like can be manufactured at low cost even in a small lot. As a result, it has become possible to make materials with a standard composition as printed matter.

  In consideration of the stable fixability of the polyamide resin with respect to PE or PP, the wetting index of the material recording portion by corona discharge machining is preferably 40 dynes or more.

  The ink receiving layer usually needs to have a thickness of 15 μm to 20 μm. Since gravure printing cannot be performed at a single thickness, it can be handled by performing printing in multiple layers. On the other hand, in the offset printing, an ink receiving layer having a desired thickness can be formed once.

  The base for forming the ink receiving layer is preferably a nonionic polyurethane resin, but is not limited thereto. For example, a known base for forming the ink receiving layer such as a cationic polyurethane resin, an acrylic-urethane resin, an acrylic resin, Polyvinyl alcohol and its modified products, polyvinyl pyrodrine, CMC, etherified starch, ethyl cellulose, nitrocellulose, water absorbent resin, polyethylene glycol, polyethylene oxide, polyacrylamide and its derivatives, styrene-butadiene copolymer, styrene-acrylic copolymer Latex and emulsion such as polymer, methyl methacrylate-butadiene copolymer and ethylene-vinyl acetate copolymer can be employed.

The base for forming the ink receiving layer is preferably further mixed with a drying aid in order to increase the drying ability and increase the surface area. Silica is preferably used as the drying aid, and organic calcium, calcium silicate, zeolite, boehmite, and aluminum hydroxide can also be used.

  The base for forming the ink receiving layer preferably contains a dye fixing agent. Examples of the dye fixing agent include polyvalent carboxylic acids and modified products thereof, such as malonic acid, succinic acid, adipic acid, maleic acid, and oxalic acid. The polyvalent carboxylic acid may be partly or wholly anhydrous. In addition, as long as it exhibits acidity as a whole, it may further contain a substituent such as a hydroxyl group or an amino group such as citric acid or aspartic acid.

  For example, an inkjet recording material is formed by flatly folding a tube-shaped material, thermocompression-bonded in a strip shape at predetermined intervals in the longitudinal direction of the material, and forming a microperforation at the center of the strip. On the other hand, it may be formed into a bag shape by cutting one end edge in the width direction of the material to form an opening.

  In addition, the ink jet recording material is formed by flatly folding a tube-shaped material, thermocompression bonding the material into a strip shape in an arbitrary shape, and forming a micro perforation in the center of the strip shape, and a part of the arbitrary shape May be formed into an arbitrary shape, for example, a heart-shaped bag shape by cutting the substrate to form an opening and separating it with a micro perforation.

  In addition, the ink-jet recording material is stacked, the two opposite sides of the quadrangle are thermocompression bonded in a linear shape, and one of the two sides is cut to form an opening, while the other two sides are heated in a strip shape. It can also be formed into a bag shape by crimping and forming a micro perforation at the center of the belt and cutting off at the micro perforation.

  In addition, the ink-jet recording material is formed by stacking materials and thermocompression bonding into a band shape in an arbitrary shape, forming a micro perforation in the center of the band shape, cutting a part of the arbitrary shape to form an opening, and micro It can also be formed into a bag shape of an arbitrary shape by separating with a perforation.

It is a figure which shows typically the first half part of the manufacturing method of preferable embodiment of the raw material for inkjet recording which concerns on this invention. It is a figure which shows typically the second half part of the manufacturing method of the said embodiment. It is a figure which shows other embodiment.

  Hereinafter, the present invention will be described in detail based on specific examples shown in the drawings. 1 and 2 show a preferred embodiment of an ink jet recording material according to the present invention. A tubular PE material 10 is used as the material, and the PE material 10 is folded flat (FIG. 1A).

  This flat PE material 10 is fed into a corona discharge device (FIG. 1B), and corona discharge machining is performed on the surface (recording location) of the PE material 10 on which printing is performed by an inkjet printer. The corona discharge uses conditions so that the wetting index on the surface of the PE material 10 is 40 dynes or more.

  A polyamide resin, for example, nylon (registered trademark) is applied to the PE material 10 subjected to corona discharge machining using a printing roll to form an anchor layer. The polyamide resin used was adjusted to a viscosity suitable for printing with a solvent such as ethanol.

  When the anchor layer is formed, an ink receiving layer is formed thereon. For the ink receiving layer, nonionic polyurethane resin 40 to 50% by weight, alcohol solvent 30 to 40% by weight, titanium oxide 1 to 15% by weight, silica 1 to 10% by weight, and succinic acid 1 to 10% by weight. What was mixed so that it might become a total of 100 weight% was used.

  The gravure printing apparatus is composed of a combination of a rolling roll 12A, a printing roll 12B having a plate formed on the surface, a resin coating roll 12C, and a resin tank 12D. Are densely formed. The feed speed is a speed within a range of 5 to 10 m / min. A nonionic polyurethane resin mixed with a silica agent adjusted to pH 7 to 9 with a pH adjuster is stored in the resin tank 12D, and this is applied to the printing roll 12D by the resin application roll 12C. Printing is performed on the anchor layer.

  Such screen printing is repeated 3 to 4 times to repeatedly coat multiple layers to form an ink receiving layer having a thickness of 15 μm to 20 μm.

  Next, as shown in FIG. 2, the material 10 is fed by a roller 15. Using a pair of brass molds 13, thermocompression bonding is performed in a strip shape at predetermined intervals in the longitudinal direction of the material 10. A flat thermocompression surface 13A is formed at the tip of the mold 13, a microphone perforation forming blade 13B is formed in the center, and a micro perforation 10B is formed in the center of the belt-like thermocompression bonding portion 10A. It is formed.

  Using the cutting blade 14, the material 10 thermocompression bonded by the brass mold 13 is cut in the immediate vicinity of the thermocompression bonding portion 10A and separated by the micro perforation 10B, whereby the material sheet 20 for ink jet recording of this example is obtained.

  Since this material sheet 20 is thermocompression bonded on the two sides and the other two sides are the folded sides of the tube, even if the material sheet 20 is set in an ink jet printer, it can be smoothly fed into the printer for printing.

  After printing, as shown in FIG. 2 (f), the printed bag 20 can be manufactured by cutting one of the folding sides of the tube along the cutting line 21.

  FIG. 3 shows a second embodiment. In this example, a heart-shaped mold 13 ′ is used as shown in FIG. 3 (a), and the material 10 is thermocompression-bonded in a belt-like shape as shown in FIG. 3 (b). A micro perforation 10B ′ is formed at the center of the portion 10A ′, and is cut at predetermined intervals to produce a material sheet 20 ′.

  After this material sheet 20 ′ is printed by an ink jet printer, it is cut along a cutting line 21 ′ as shown in FIG. 3 (c), and a micro perforation 10B ′ as shown in FIG. 3 (d). When it is cut off, a printed heart-shaped bag can be obtained.

  In addition, although the case where a tube-shaped raw material was used was demonstrated in said example, also when using two raw materials in piles, a bag can be manufactured similarly. In the above example, the case of manufacturing a PE bag has been described. However, the present invention can also be applied to the case of manufacturing a PE film or sheet, a PP bag, or a film or sheet. In addition, even when printing on a three-dimensional object such as a doll, if the ink receiving layer of the present invention is formed, it can also be printed by an ink jet printer.

DESCRIPTION OF SYMBOLS 10 Tubular material 10A Thermocompression bonding part 10B Microperforation 11A, 11B Electrode 12B Printing roll 13 Electrode 20 Material sheet

Claims (4)

An inkjet recording material made of polyethylene or polypropylene having excellent recording characteristics by an inkjet printer,
Corona discharge machining is performed on the recording portion of the material, an anchor layer made of a polyamide resin is formed on the corona discharge machining portion, and an ink receiving layer is formed on the anchor layer. Inkjet recording material.   2. A material for ink jet recording according to claim 1, wherein the material recording location by corona discharge machining has a wetting index of 40 dynes or more.   2. The ink jet recording material according to claim 1, wherein the base for forming the ink receiving layer is a nonionic polyurethane resin. The ink jet recording material according to claim 1, wherein the ink receiving layer is adjusted to a pH of 7 to 9.

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