JP5141803B2 - Inkjet printed matter, method for producing the same, and packaging material comprising the same - Google Patents

Description

  The present invention relates to a printed matter that is subjected to ink jet printing on a plastic substrate and further exhibits an overcoat treatment, thereby exhibiting good packaging suitability, and more specifically, excellent adhesion between the ink receiving agent and the plastic substrate. Ink-jet printed matter that can be used as a packaging material without any problems such as ink bleeding after printing, squeezing, dropping, peeling or peeling of the ink receiving layer and overcoat treatment layer, and its production method, and It relates to a packaging material.

  Advances in the technology of inkjet color printers that produce color hard copies at high speed have made it possible to obtain clear images and excellent print quality. On the other hand, in order to further improve the print quality, saturation, appearance, and image, a recording material having more advanced characteristics is required. In particular, along with improvements in printing speed, resolution, saturation, etc., advanced characteristics such as quick drying of ink, high absorption capacity, control of dot diameter / bleeding and surface gloss, etc. are also available for recording materials. Is required.

  The ink-jet recording material using paper as a support has a problem that the appearance is deteriorated due to occurrence of a phenomenon called cockling in which the support is waved when touched with water or tearing. In order to solve such a problem, it has been proposed to use an ink jet recording medium having a plastic film itself as a support and an ink receiving layer thereon, and to perform printing (for example, Patent Document 1). ~ 4). Such a medium is excellent in water resistance and can be used as an outdoor advertisement, a poster, a label, wallpaper, or the like. However, the surface of these plastic films that come into contact with the ink receiving agent has poor adhesion to the ink receiving agent, and layers usually referred to as an anchor layer, primer layer, undercoat layer, adhesive layer, etc. The surface treatment process to be formed is essential. Such a surface treatment step not only leads to an increase in cost, but also requires a lot of time for production because it increases one step compared with the case where the treatment is not performed. Furthermore, when the surface treatment is performed by application of a paint containing a solvent, a step for removing the contained solvent is required, and when the solvent is an organic solvent, the burden on the environment is increased.

  As a method for solving the above problem, an inkjet image receiving sheet is disclosed in which an ink receiving agent is directly applied to a thermoplastic resin film having a laminated structure of two or more layers as a support (see, for example, Patent Document 5). ). However, since the surface of the sheet specifically provided in Patent Document 5 is high-density polyethylene, it may be difficult to finish the printing neatly when the ink receiving agent is applied, There was a problem that the printed part was peeled off due to the change in the adhesiveness between the receiving agent and the substrate (film) over time.

  Conventionally, in order to prevent the contents from being contaminated, printing of a packaging material is often used with a simple configuration in which ink is printed only on the front side of the printing material and not printed on the back side in contact with the contents. . This method is called a surface printing method. However, in the surface printing method, printing may be distorted or dropped due to impacts such as rubbing, and when it is heat-sealed during packaging, ink is taken off the seal bar, printing is peeled off, and the packaging machine is contaminated In the case of a packaging material having an ink receiving layer, the ink receiving layer may be cracked, resulting in poor appearance. As a method for preventing this, a so-called overcoat treatment in which a protective layer (film) is bonded to the image surface of the printed matter or coated with a coating agent is known and used depending on the use of the produced printed matter. (For example, see Patent Documents 6 to 7). However, unless the adhesion between the plastic film and the receiving agent is ensured, if these overcoat treatments are performed, the printing surface will still peel or bleed during the operation, which is fundamental. It is not a solution.

Japanese Patent Laid-Open No. 10-119428 JP 2001-150612 A Japanese Patent Laid-Open No. 2002-103802 JP 2007-130780 A JP 2002-011937 A JP 2006-035796 A JP 2002-144551 A

  An object of the present invention is made in view of the above problems, and it is possible to uniformly apply an ink receiving agent without performing an essential surface treatment step when using a conventional plastic film as a base material. In addition, due to the excellent adhesion between the plastic film and the receiving agent, problems such as peeling after ink jet printing do not occur, and ink bleeding, dripping, dropping, peeling or ink receiving layer and overcoat during overcoat treatment An object of the present invention is to provide an ink-jet printed matter free from problems such as peeling of the treatment layer, a method for producing the same, and a packaging material comprising the same.

  As a result of intensive studies to solve the above problems, the inventors of the present invention have found that a layer (A1) containing a polyolefin resin (a1) as a main component and a layer (A2) containing an acid-modified olefin resin (a2). The present invention has been completed by finding that the above-mentioned problems can be solved by using as a support a multilayer film in which and are laminated.

  That is, in the present invention, the layer (A1) containing the polyolefin resin (a1) as a main component, the layer (A2) containing the acid-modified olefin resin (a2), and the ink receiving layer (B) are: An ink-jet printed matter obtained by performing ink-jet printing on the layer (B) of the ink-jet recording medium laminated in the order of A1) / (A2) / (B) and performing an overcoat treatment on the printed surface. And a manufacturing method thereof, and a packaging material using the same.

  The ink jet printed matter of the present invention can be easily obtained by applying an ink receiving agent on a coextruded multilayer film, printing, and overcoating. The design can be easily changed by selecting the layer structure of the multilayer film according to the target performance (transparency, rigidity, workability, etc.) and application (packaging material, poster, label, etc.). Excellent. The printed matter obtained can be stored for a long period of time due to the good adhesion between the ink-receiving layer and the multilayer film as the base material. Since peeling does not occur, it may be used as it is, and this printed matter can be used as a packaging material for bags and the like by secondary processing.

  The plastic film functioning as a support for the inkjet printed matter of the present invention has at least a layer (A1) mainly comprising a polyolefin resin (a1) and a layer (A2) containing an acid-modified olefin resin (a2). Is. This layer (A2) functions not only as a support but also as an easily adhesive layer with the ink receiving layer (B). In the present invention, “main component” means that the specific resin is contained in an amount of 80% by mass or more based on the total amount of the resin composition forming the layer, and preferably 85% by mass. The above is a specific resin. Further, in the present invention, “containing” means that the specific resin is contained in an amount of 1% by mass or more with respect to the total amount of the resin composition forming the layer, and preferably 20% by mass or more. Say that it is a specific resin.

  The opposite side of the overcoat layer (C) of the inkjet printed material of the present invention is a layer (A1) mainly composed of a polyolefin resin (a1). Examples of the polyolefin-based resin (a1) that can be used here include homopolymers or copolymers of α-olefins having 2 to 6 carbon atoms. The copolymerization type may be a block copolymer or a random copolymer. In addition, the polyolefin resin (a1) has a melting point of 110 ° C. or more from the viewpoint of maintaining the appearance at the time of overcoat treatment or molding when used as a packaging material, and suppressing warpage of the film itself. It is preferable to use it.

  As the polyolefin resin (a1), for example, any of those known as polypropylene resin, polyethylene resin and the like can be used. For example, as a polypropylene resin, a propylene homopolymer, a propylene-ethylene copolymer, a propylene-butene-1 copolymer, a propylene-ethylene-butene-1 copolymer, an ethylene-propylene block copolymer, a metallocene catalyst And polypropylene. These may be used alone or in combination of two or more. When the inkjet recording medium before inkjet printing is wound into a roll and stored for a long period of time, it is preferable to use a crystalline propylene-based resin from the viewpoint of preventing blocking. In addition, in this application, crystallinity means having a peak of 0.5 J / g or more in the range of 95-250 degreeC in DSC (differential scanning calorimetry).

The polypropylene resin has a melt flow rate (hereinafter referred to as “230 ° C. MFR”; a value measured at 230 ° C. and 21.18 N in accordance with JIS K7210: 1999) of 0.5 to 30. Those having a melting point of 120 to 165 ° C. at 0.0 g / 10 min are preferred, and more preferably those having an MFR of 230 ° C. of 2.0 to 15.0 g / 10 min and a melting point of 125 to 162 ° C. . If the MFR and the melting point are in this range, the film itself is less contracted during overcoating after printing or when heat forming when used as a packaging material. Thus, the film formability of the coextruded multilayer film is improved. It is preferable that density is 0.890~0.910g / cm ^3, more preferably 0.895~0.905g / cm ^3.

  In particular, when a propylene-ethylene block copolymer is used for the layer (A1), the surface is modified into a satin finish, and the generation of wrinkles when winding the multilayer film into a roll can be suppressed. Blocking when stored in roll form can be reduced. Here, the propylene-ethylene block copolymer is a resin obtained by block polymerization of propylene and ethylene. For example, propylene obtained by polymerizing ethylene or ethylene and propylene in the presence of a propylene homopolymer. -An ethylene block copolymer etc. are mentioned.

  Further, when a mixed resin of crystalline propylene resin and ethylene / propylene rubber (hereinafter referred to as “EPR”) is used for the layer (A1), the surface of the layer (A1) can be easily modified into a satin finish. Can do. As the crystalline propylene-based resin used at this time, a highly versatile propylene homopolymer is preferable. On the other hand, as the EPR used at this time, those having a weight average molecular weight in the range of 400,000 to 1,000,000 are preferable in that irregularities are formed on the film surface and the surface can be modified into a satin finish, A range is more preferable. In addition, the EPR content in the mixed resin is preferably in the range of 5 to 35% by mass in that the film surface can be uniformly modified into a satin finish. The MFR (230 ° C.) of the mixed resin of the crystalline propylene polymer and EPR is preferably in the range of 0.5 to 15 g / 10 minutes from the viewpoint of easy extrusion. In addition, the weight average molecular weight of the EPR was obtained by calculating a component extracted from the mixed resin by a cross fractionation method at 40 ° C. using orthodichlorobenzene as a solvent by GPC (gel permeation chromatography). It is. The content of EPR in the mixed resin is obtained from the amount of EPR extracted by cross-fractionation at 40 ° C. using orthodichlorobenzene as a solvent.

  The method for producing the mixed resin of the crystalline propylene-based resin and EPR is not particularly limited. As a specific example, for example, a propylene homopolymer and ethylene / propylene rubber are separately mixed using a Ziegler type catalyst. After producing by a combination method, a slurry polymerization method, a gas phase polymerization method, etc., a propylene homopolymer is produced in the first stage by a method of mixing both with a mixer or a two-stage polymerization method, and then the second stage. And a method of generating EPR in the presence of this polymer.

  The Ziegler-type catalyst is a so-called Ziegler-Natta catalyst, and is obtained by supporting a transition metal compound such as a titanium-containing compound or a transition metal compound on a support such as a magnesium compound. The combination with the promoter of an organometallic compound is mentioned.

Examples of the polyethylene resin include medium density polyethylene (MDPE) and high density polyethylene (HDPE), and the density is preferably 0.92 to 0.97 g / cm ³ . When the density is within this range, the film has an appropriate rigidity and improves film formability and extrusion suitability. Moreover, it is preferable that it is 2-20 g / 10min, and, as for MFR (190 degreeC, 21.18N) of a polyethylene-type resin, it is more preferable that it is 3-10 g / 10min. When the MFR is within this range, the extrudability of the film is improved, the generation of wrinkles that are likely to occur when the multilayer film is rolled up can be suppressed, and the roll-out property from the roll is excellent. Furthermore, these polyethylene resins preferably have a melting point of 110 to 135 ° C, more preferably a melting point of 115 to 130 ° C. If the melting point is within this range, the film has little shrinkage even when heated by over-coating after printing or secondary molding when used as a packaging material, so the appearance of the printed surface can be maintained. Warpage of the film itself can be suppressed. These may be used alone or in combination of two or more.

  As a layer (A1) which has polyolefin resin (a1) as a main component, it may be a single layer or may have a multilayer structure of two or more layers. From the viewpoint of more excellent rigidity and heat resistance and excellent workability when the printed material is secondarily processed, a film having a single layer or a multilayer structure mainly composed of a polypropylene resin is preferable. For example, when using a printed matter as a package, the outermost layer on the opposite side of the overcoat layer (C) is composed of 1-butene and propylene as essential components as described in JP-A-2006-213065. It can be set as an easily openable bag by setting it as the heat seal layer containing the 1-butene-type copolymer and the copolymer which has propylene and ethylene as an essential component. Similarly, when used as a lid, it can be easily opened by adopting a multilayer structure as described in JP-A-2004-75181 and JP-A-2008-80543. It is. Furthermore, when a cyclic polyolefin resin as described in JP 2010-234660 A is used as one layer in a multilayer structure, it is possible to obtain a printed material having easy tearability, depending on the use of the printed material. It is preferable to employ various multilayer configurations.

  Moreover, it can also be set as the inkjet printed material (label) which can be affixed on a signboard, a vehicle, etc. by providing an adhesive layer on a layer (A1) [surface opposite to layer (A2) mentioned later]. The type of the adhesive is not particularly limited. For example, natural rubber, synthetic rubber, acrylic, urethane, vinyl ether, silicone, amide and styrene adhesive, styrene elastomer, olefin elastomer Etc. For the purpose of controlling the adhesive properties, etc., the pressure-sensitive adhesive layer may include, for example, terpene resins such as α-pinene, β-pinene polymer, diterpene polymer, α-pinene / phenol copolymer, fat Appropriate tackifiers such as aromatic resins, aromatic resins, aliphatic / aromatic copolymer systems, other rosin resins, coumarone indene resins, (alkyl) phenol resins and xylene resins Can be blended. Among these, when laminating a layer (A1) and a layer (A2) to be described later by a coextrusion method, a method of simultaneously laminating an adhesive layer on the layer (A1) opposite to the layer (A2) by coextrusion Is preferable in the manufacturing cycle.

  The layer (A2) in the present invention is a layer containing the acid-modified olefin resin (a2) as an essential component. Although the olefin component which is the main component of the acid-modified polyolefin resin (a2) is not particularly limited, it has 2 to 6 carbon atoms such as ethylene, propylene, isobutylene, 2-butene, 1-butene, 1-pentene, 1-hexene and the like. Alkenes are preferred and mixtures of these may be used. Among these, alkene having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene and 1-butene is more preferable, ethylene and propylene are further preferable, and ethylene is most preferable. Moreover, the acid-modified polyolefin resin (a2) needs to contain a (meth) acrylic acid ester component. (Meth) acrylic acid ester components include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic acid Examples include octyl, decyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, and the like. From the viewpoint of easy availability and adhesiveness, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and hexyl acrylate are more preferable, and methyl acrylate and ethyl acrylate are more preferable. The (meth) acrylic acid ester component may be copolymerized with the olefin component, and the form thereof is not limited. Examples of the copolymerization state include random copolymerization, block copolymerization, and graft copolymerization. (Graft modification) and the like. (In addition, "(meth) acrylic acid ~" means "acrylic acid ~ or methacrylic acid ~".) Specifically, as an ethylene- (meth) acrylic acid ester copolymer, for example, Elvalloy ( Product name: Mitsui-DuPont Polychemical Co., Ltd.), Aklift (trade name: Sumitomo Chemical Co., Ltd.), etc. These may be used alone or in combination of two or more.

  Further, the acid-modified polyolefin resin (a2) may be acid-modified with an unsaturated carboxylic acid component. Examples of unsaturated carboxylic acid components include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, and the like, as well as unsaturated dicarboxylic acid half esters and half amides. It is done. Of these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable. The unsaturated carboxylic acid component may be copolymerized with the olefin component, and the form thereof is not limited. Examples of the copolymerization state include random copolymerization, block copolymerization, and graft copolymerization (grafting). Modification). Specifically, examples of the ethylene-acrylic acid copolymer include Nucrel (trade name: Mitsui / DuPont Polychemical Co., Ltd.). Examples of the ethylene- (meth) acrylic acid ester-maleic anhydride copolymer include bondine (trade name: manufactured by Tokyo Materials Co., Ltd.). These may be used alone or in combination of two or more.

  The acid modification rate of the acid-modified olefin resin (a2) includes adhesion to the ink receiving agent (b) described later, suppression of blocking when winding and storing the multilayer film, and ink receiving agent (b). It is preferable to use 3 to 40%, more preferably 7 to 35%, from the viewpoint of excellent balance such as suppression of appearance defects such as wrinkles of the film in the drying step after coating. 30% is particularly preferred.

  In the layer (A2) in the present invention, in addition to the acid-modified olefin resin (a2), other resins may be used in combination. In particular, it is preferable to use a polyolefin-based resin in combination because it is mixed with the acid-modified olefin-based resin (a2) and can be easily coextruded with the layer (A1). At this time, the acid-modified olefin resin (a2) is preferably contained in an amount of 20 parts by mass or more, particularly preferably 50 parts by mass or more in 100 parts by mass of the resin component forming the layer (A2).

  As the polyolefin resin, any of those exemplified for the polyolefin resin (a1) used for the layer (A1) can be suitably used. At this time, the polyolefin resin used in the layer (A1) and the layer (A2) may be the same or different. The polyolefin resin used in the layer (A2) may be a single resin or a mixture of plural kinds.

  In each of the layers (A1) and (A2), an antifogging agent, an antistatic agent, a thermal stabilizer, a nucleating agent, an antioxidant, a lubricant, an antiblocking agent, a release agent, and an ultraviolet absorber are added as necessary. Components such as a colorant and a colorant can be added within a range that does not impair the object of the present invention. In particular, the surface friction coefficient is preferably 1.5 or less, more preferably 1.0 or less in order to impart processing suitability when forming a film or packaging suitability when a printed material is used as a packaging material. It is preferable to add a lubricant, an antiblocking agent or an antistatic agent to the resin layer corresponding to the layer as appropriate.

  The total thickness of each of the layers (A1) and (A2) can be set as appropriate according to the use of the printed matter. For example, when the packaging material (bag or lid material) is used, the thickness is 20 to 50 μm. In the case of labels and posters, it is preferably in the range of 70 to 1000 μm. Further, the ratio of the thickness of the layer (A2) to the total thickness of the layers (A1) and (A2) is in the range of 5 to 40% from the viewpoint of ensuring adhesion with the ink receiving layer described later. Preferably, the thickness of the layer (A2) is preferably in the range of 2 to 30 μm.

  As a method of laminating the layer (A1) and the layer (A2), it is necessary to be a coextrusion laminating method in which the layer (A1) and the layer (A2) are laminated adjacently. After laminating the layers (A1) and (A2) in a molten state by various coextrusion methods such as a coextrusion multilayer die method and a feed block method, which are melt extruded using two or more extruders, inflation, A method of processing into a long wound film by a method such as a T-die / chill roll method is preferred, and a co-extrusion method using a T-die is more preferred.

  Further, it is desirable that the surface of the layer (A2) is continuously subjected to surface treatment using corona discharge or plasma discharge under heating or in an inert gas atmosphere during the production of the multilayer film.

  The ink-jet printed material of the present invention is obtained by applying various ink receiving agents (b) on the multilayer film obtained above, and then volatilizing the medium contained in the ink receiving agent (b). After the receiving layer (B) is formed, printing is performed on the receiving layer (B), and an overcoat layer (C) is further laminated.

  The ink receiving layer (B) of the ink-jet printed material of the present invention accepts ink having a thickness in the range of 3 μm to 50 μm in order to maintain properties such as ink absorbability at a practical level and maintain good production efficiency. Those having a layer (B) are preferred, and those having an ink receiving layer (B) having a thickness in the range of 5 μm to 30 μm are more preferable in consideration of the ink absorbability and the coating strength of the ink receiving layer (B). .

  A method for coating the ink receiving agent (b) on the film is not particularly limited. For example, a coating machine such as an air knife coater, a blade coater, a roll coater, a gravure coater, a comma coater, or a gate roll coater is used. The method used is simple.

  The method of volatilizing the medium contained in the receiving agent after coating the ink receiving agent (b) on the film is not particularly limited, but for example, a method of drying using a dryer. It is common. The drying temperature may be a temperature that can volatilize the medium and does not adversely affect the substrate.

  The ink receiving agent (b) is not particularly limited, and can be appropriately selected according to the type of ink-jet ink. In particular, in the present invention, it is necessary to provide a receiving layer having high ink absorption performance, printing performance, and water resistance of printed images from the viewpoint of forming an ink receiving layer on the multilayer film layer (A2).

  As an ink-jet receiving layer, a recording material containing a large amount of inorganic porous particles called microporous or void type has been proposed. However, cracking in a process of coating on a substrate, especially a plastic substrate, is proposed. There is a problem that adhesion to the material is low. As an example for solving such a problem, a recording material containing various anionic polyurethane resins having excellent substrate adhesion is exemplified (Japanese Patent Laid-Open No. 2002-317116).

  Further, in recent years, there has been a demand for high added value of printed matter, and in order to realize high image quality (high gloss) similar to silver salt photography, a recording material containing a cationic polyurethane resin excellent in gloss and transparency (Japanese Patent Laid-Open No. 2007-168164). In this invention, it is preferable that it is a receiving agent containing a polyurethane resin from the point which uses as a base material the plastic film in which high design property is calculated | required.

  Examples of the cationic polyurethane resin include a tertiary amino group obtained by reacting a polyisocyanate, a polycarbonate polyol, a tertiary amino group-containing chain extender, and a polyalkylene oxide having 50% by mass or more of an ethylene oxide chain. Examples thereof include a cationic aqueous polyurethane resin obtained by dispersing a quaternized urethane prepolymer in water, and a polyurethane resin having a cationic group in a side chain provided in JP-A No. 2007-168164. .

  Since polyurethane resins having these polar groups are often aqueous dispersions, when used as an ink receiving agent, a water-based resin is usually used in combination as a binder resin.

  A water-soluble resin can be used as the binder resin, such as polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyacrylic acid, polyhydroxyethyl acrylate, polyacryloylmorpholine, water-soluble polyvinyl acetal, poly-N-vinylacetamide, poly-N. -Vinylformamide, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose, hydroxyethylmethylcellulose, carboxymethylcellulose, gelatin, casein, starch and the like can be exemplified and can be used alone or in combination. Polyvinyl alcohol is particularly preferable.

  The saponification degree of polyvinyl alcohol is particularly preferably 70 mol% or more, and most preferably 85 mol% to 90 mol%. When polyvinyl alcohol having a saponification degree exceeding 90 mol% is used, the compatibility with the urethane resin tends to decrease, and as a result, the gloss of the receiving layer itself may decrease. Polyvinyl alcohol having any degree of polymerization can be used, but a range of 500 to 4000 is preferable from the viewpoint of improving ink absorbability, color density, and water resistance. The polyvinyl alcohol may be modified polyvinyl alcohol having various modifying groups as long as the saponification degree and the polymerization degree are within the above ranges. Examples of the modifying group include acetoacetyl group, silyl group, quaternary ammonium base, carboxylic acid group, carboxylic acid group, sulfonic acid group, sulfonic acid group, ketone group, mercapto group, amino group, ethylene group, and the like. It is done. These can be introduced into polyvinyl alcohol by copolymerizing vinyl acetate and a monomer having the modifying group.

  Moreover, you may use aqueous resin emulsions other than the said polyvinyl alcohol as binder resin. For example, polyvinyl pyrrolidone, polyvinyl acetal, polyalkylene oxide, starch, methylcellulose, hydroxycellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, cellulose derivatives such as carboxymethylcellulose, polyethyleneimine, polyamide, various quaternary ammonium base-containing water-soluble resins , And modified products thereof, epichlorohydrin polyamide resin, amine epichlorohydrin resin, polyethyleneimine salt-containing resin, polyvinylamine salt-containing resin, polyvinylamidine resin, polyallylamine salt-containing resin, polyaminesulfone salt-containing resin, polydiallyldimethylammonium chloride, Dicyandiamide-formalin polycondensate, cation-modified polyvinyl alcohol, cation Group-containing water-soluble acrylic resin, cationically modified starch, a water-soluble resin such as neutralization salts of chitosan may be used. Furthermore, conjugated diene polymer latex such as styrene-butadiene copolymer and methyl methacrylate-butadiene copolymer, vinyl copolymer latex such as acrylic polymer and styrene-vinyl acetate copolymer, polyurethane latex An aqueous emulsion such as polyester latex can be used.

  Further, in order to obtain an ink jet printed matter having a high ink absorption speed and excellent quick drying properties, an ink receiving agent containing a large amount of porous inorganic fine particles called a microporous type or a void type may be used. Examples of the porous inorganic fine particles include pseudo boehmite type alumina and silica produced by a gas phase method. By containing such inorganic fine particles, the ink receiving layer (B) has innumerable fine voids, and the voids absorb the ink solvent to enable printing.

  Further, when a pigment-based inkjet ink is used, it is preferable to contain a water-soluble polyvalent metal salt in the ink receiving agent (b). The water-soluble polyvalent metal salt here is a polyvalent metal salt having solubility in water. For example, when a saturated aqueous solution of the polyvalent metal salt is prepared using water at 20 ° C., it is contained in 100 g of the saturated aqueous solution. The polyvalent metal salt is 1 g or more. Examples of water-soluble polyvalent metal salts include divalent metal salts such as magnesium salts, calcium salts, barium salts, iron (II) salts, copper (II) salts, and zinc salts, aluminum salts, and chromium salts. A trivalent metal salt can be used.

  By using such a water-soluble polyvalent metal salt, the absorbability of the pigment ink can be improved and the water resistance of the printed matter can be improved. Of the water-soluble polyvalent metal salts, it is preferable to use water-soluble magnesium salts from the viewpoint that the effect of improving the absorption of the pigment ink is high. For example, magnesium chloride, magnesium acetate, magnesium nitrate, magnesium sulfate, magnesium chlorate, etc. Can be used. Only one type of these may be used, or two or more types may be used. Of the water-soluble magnesium salts, magnesium chloride is particularly preferred because of its good solubility in water, its low cost and easy availability, and its high four effects.

  The ink receiving agent (b) is further blended with an ultraviolet absorber and / or a hindered amine light stabilizer for the purpose of improving the weather resistance when printed matter is used under long-term and severe conditions outdoors. It is preferable.

  Examples of the ultraviolet absorber include 2- (2′-hydroxy-3′-lauryl-5′-methylphenyl) benzotriazole, methyl-3- [3-t-butyl-5- (2H-benzotriazole-). 2-yl) -4-hydroxyphenyl] propionate-polyethylene glycol condensates and hydroxyphenylbenzotriazole derivatives.

  Examples of the hindered amine light stabilizer include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), dimethyl succinate-1 -(2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate and poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3 , 5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino }] Etc. It is.

  Even when each of the ultraviolet absorber and the hindered amine light stabilizer is used alone or in combination, it is preferably in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin component in the receiving agent (b).

  Furthermore, in the receiving agent (b), other synthetic resins, pigments, water-resistant agents, dispersants, antifoaming agents, etc. are blended depending on the use of the printed matter within a range not impairing the purpose of the present invention. Can do.

  The inkjet printed matter of the present invention is obtained by applying various ink receiving agents (b) on the multilayer film obtained above, printing on the receiving layer, applying an overcoat treatment, and overcoat layer (C). Are laminated.

  Examples of the inkjet ink that can be used here include water-based dye ink, water-based pigment ink, solvent / oil-based ink, ultraviolet curable ink, and heat-melt ink. Of these, the use of water-based pigment inks is preferred, and water-soluble or water-dispersible organic resins are generally used. Examples of the resin include water-soluble acrylic resin, polyester resin, polyether resin, cellulose resin, polyamide resin, and polyvinyl alcohol resin. Natural polymers may also be used. Specific examples thereof include proteins such as gelatin, casein and albumin, and natural rubbers such as gum arabic.

  The printing method is preferably ink jet printing, but printing may be performed by other printing methods such as offset printing, letterpress printing, gravure printing, silk screen printing, or a combination of these two or more printing methods. It doesn't matter. For offset printing, letterpress printing, gravure printing, and silk screen printing ink, an ultraviolet curable ink is often used because of the problem of printing durability, and is preferable.

  As for the overcoat treatment method, for example, a method of polymerizing (crosslinking) the components of the overcoat by drying and / or heating or applying ultraviolet rays or a low-voltage electron beam, a thermoplastic resin film as a main component with a heated roller And a method of heat-transferring the film, and a method of overcoating by laminating the film via an adhesive. The overcoat treatment method is not particularly limited as long as it can improve various durability such as heat resistance, water resistance and weather resistance of the printed matter. From the viewpoint of adhesion to the receiving agent, an overcoat by UV curable ink jet, an overcoat by application of a liquid coating solution, and an overcoat by laminating a stretched or unstretched resin film via an adhesive are preferred, and an adhesive An overcoat treatment by laminating a stretched or unstretched resin film via is most preferred.

  Examples of the overcoat treatment adhesive include ester adhesives, ether adhesives, urethane adhesives, epoxy adhesives, acrylic adhesives, methacrylic adhesives, vinyl acetate adhesives, and olefin adhesives. , Silicone adhesives, isocyanate adhesives, styrene adhesives, etc., preferably ester adhesives, ether adhesives, urethane adhesives, acrylic adhesives, methacrylic adhesives, More preferred are ester adhesives and ether adhesives. Examples of commercially available products include ester adhesive “LX500” manufactured by DIC Corporation, and ether adhesive “LX401A” manufactured by DIC Corporation.

  Examples of the stretched or unstretched resin film for the overcoat treatment include stretched polypropylene film, stretched nylon film, stretched polyester film, stretched polystyrene film, unstretched polyethylene film, unstretched polypropylene film, PVC film, PVDC film, and acrylic film. Is mentioned. A stretched polypropylene film, a stretched nylon film, and a stretched polyester film are preferably used. Commercially available products include stretched polypropylene film “Pyrene Film-OT” manufactured by Toyobo Co., Ltd., stretched nylon film “Harden Film” manufactured by Toyobo Co., Ltd., stretched polyester film “Soft Shine” manufactured by Toyobo Co., Ltd., and the like.

  The UV curable inkjet for the overcoat treatment, the liquid coating solution, and the resin film may further contain a light resistance improver to further improve the light resistance of the printed matter and the (A1) / (A2) This is preferable from the viewpoint of preventing deterioration of the ink jet recording medium itself composed of / B. The light fastness improver is not particularly limited as long as it has an action of suppressing discoloration and fading of a recorded image by ultraviolet light or visible light, and is preferably used in combination with a receiving agent. HALS), and one or more selected from the group consisting of antioxidants and quenchers (quenching agents).

  Examples of the antioxidant include phenols such as hindered phenols, chromanes, clamans, hydroquinone derivatives, benzotriazoles (those having no ultraviolet absorption ability), and spiroindanes.

  Examples of the quencher include inorganic metal complexes such as nickel and cobalt.

  Even when the light resistance improver is used alone or in combination in the overcoat material, it is preferably contained in an amount of 0.01 to 30% by mass, more preferably 0.1 to 20% by mass.

  Examples of the packaging material comprising the inkjet printed material of the present invention include packaging bags, containers, container lid materials, and the like used for foods, medicines, industrial parts, miscellaneous goods, magazines and the like. In particular, it can be suitably used for medicines, industrial parts, foods and confectionery stored at room temperature, refrigerated and frozen, which are filled, packaged and sealed at high speed. Moreover, it is not a packaging material, and there is no problem even if it is used for various purposes such as outdoor advertisements (posters, banners, etc.), labels, wallpaper, postcards, OHP sheets, lottery tickets, forms, and the like.

  The packaging material is heat-sealed with the layer (A1) of the multilayer film of the present invention as a heat-sealing layer, and the layers (A1) are laminated one after another, or the layer (A1) and the overcoat layer (C) are laminated. It is preferable that it is a packaging bag formed with the layer (A1) as the inner side by sealing. For example, after cutting the two printed materials after overcoating into the desired size of a packaging bag, overlapping them, heat-sealing three sides to form a bag, and then starting from one side that is not heat-sealed It can be used as a packaging bag by filling the product, heat sealing and sealing. Furthermore, it is also possible to form a packaging bag by sealing the upper and lower sides after sealing the end of a roll-shaped film into a cylindrical shape by an automatic packaging machine.

  It is also possible to form a lid of a packaging bag / container / container by heat-sealing with the layer (A1) and another film, sheet, or container that can be heat-sealed. In that case, as another film to be used, a film or sheet using a thermoplastic resin such as a polyethylene resin, a polypropylene resin, or a polyester resin can be used.

  In the packaging material using the printed matter after the overcoat treatment of the present invention, any tear such as V-notch, I-notch, perforation, micro-porosity, etc. is used in the seal portion in order to weaken initial tear strength and improve openability. A starting portion may be formed.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these. In the examples, “part” and “%” are based on mass unless otherwise specified.

[Evaluation of coating suitability of ink receiving layer]
A receiving agent was applied to an A4 size film with a bar coater so as to be 10 g / m ^2, and the number of repellings was visually measured.
○: No repelling.
X: There are one or more repels.

[Evaluation of heat resistance of film]
After coating the receiving agent, the appearance of the film was visually evaluated when dried at 80 ° C. for 5 minutes.
○: Almost no defects in appearance such as kinks, wrinkles and film deformation.
Δ: Appearance defects such as slight kinks, wrinkles and film deformation are observed.
X: Appearance defects such as significant kinks, wrinkles, and film deformation are observed.

[Evaluation of printability]
It was visually evaluated whether stable ink transfer (printing) was performed on the ink receiving layer.
○: Printed satisfactorily with no prints or no printable parts.
×: Printing is faint or there are parts that cannot be printed, and there is a printing defect.

[Adhesion evaluation after overcoat treatment]
An adhesive was applied to the printed receiving layer (B), and a stretched resin film was laminated. A test piece was cut into a strip shape so that the obtained printed matter had a width of 15 mm, and the test piece was 300 mm using a tensile tester (manufactured by A & D Co., Ltd.) in a thermostatic chamber at 23 ° C. and 50% RH. The peel strength was 90 ° peeled at a rate of / min and the interlayer strength was measured. From the obtained value of interlayer strength, adhesion was evaluated according to the following criteria.
○: Interlayer strength is 200 g / 15 mm width or more.
X: Interlayer strength is less than 200 g / 15 mm width.

Suitability for packaging machine The printed products prepared in the examples and comparative examples were subjected to the following vertical pillow packaging with an automatic packaging machine, and were made into bags.
Packaging machine: Rika Kaken Co., Ltd. Unipacker NUV472

  Horizontal sealing: Resin layers (B) were sealed while changing at a rate of 30 bags / minute, a vertical heat seal temperature of 150 ° C., an air gauge pressure of 4 kg / cm 2, and a horizontal heat seal temperature of 140 ° C. to 190 ° C. in increments of 10 ° C. A flat bag measuring 200 mm long and 150 mm wide was used.

Shrinkage / Wrinkle Test The appearance of the sealed portion of the flat bag which was subjected to horizontal (gap-attached) seal and vertical seal was evaluated by shrinkage and the state of film fusion to the heat seal bar and the condition of wrinkles.
○: There is no shrinkage of the seal part, fusion to the seal bar and wrinkles, etc. Δ: There is some shrinkage of the seal part, fusion to the seal bar and wrinkles, etc. ×: Shrinkage of the seal part, fusion to the seal bar and wrinkles Etc.

Lateral sealing property The printed matter produced under the above conditions was naturally cooled at 23 ° C., and then a test piece was cut into a strip shape having a width of 15 mm. The test piece was peeled 90 ° at a rate of 300 mm / min using a tensile tester (manufactured by A & D Co., Ltd.) in a thermostatic chamber at 23 ° C. and 50% RH, and the heat seal strength was measured. The heat sealability was evaluated according to the following criteria from the obtained heat seal strength value.
○: Heat seal strength is 300 g / 15 mm width or more.
X: Heat seal strength is less than 300 g / 15 mm width. Or the melt / shrinkage of the film is too large to be measured or delamination occurs.

[Ink Receiving Agent Preparation Example 1]
25% by mass aqueous solution of hydran CP-7020 (manufactured by DIC Corporation, cationic polyurethane resin aqueous dispersion) and PVA205 [manufactured by Kuraray Co., Ltd., saponification degree 87 mol% to 89 mol%, polymerization degree 500 polyvinyl alcohol] And a 53.5 mass% aqueous solution of magnesium chloride hexahydrate, and a 25 mass% aqueous solution of DK-6830 [manufactured by Seiko PMC Co., Ltd., epichlorohydrin polyamide resin], [water dispersion: 25 mass% aqueous solution of PVA205. : 53.5 mass% aqueous solution of magnesium chloride hexahydrate: 25 mass% aqueous solution of DK-6830] so that the mass ratio is 48.2: 35.9: 3.0: 12.9. The ink receiving agent (b-1) containing a cationic polyurethane resin was prepared by thoroughly mixing with a stirrer equipped with a propeller blade.

[Ink Receiving Agent Preparation Example 2]
10 parts of magnesium chloride, 30 parts of hydran HW-970 (manufactured by DIC Corporation, polyurethane resin aqueous dispersion having a sulfonic acid group as a polycarbonate chain and a hydrophilic group, non-volatile content 40%), Goseifamer Z-100 (Nippon Synthetic Chemical) 30 parts of a 20% aqueous solution of acetoacetylated polyvinyl alcohol (manufactured by Co., Ltd.) and 30 parts of WS525 (manufactured by Seiko PMC Co., epichlorohydrin polyamide resin) are blended, and contains an anionic polyurethane resin having a nonvolatile content of 15% by mass. An ink receiving agent (b-2) was prepared.

  Regarding ink jet printing, ink jet printing was performed on the ink receiving layer (B) using an eight-color ink jet printer (manufactured by Seiko Epson Corporation). Ink jet printing ink was a pigment type exclusive ink manufactured by Seiko Epson Corporation.

Example 1
As the resin for the resin layer (A1), a propylene-ethylene copolymer [MFR: 8 g / 10 min (230 ° C., 21.18 N), melting point: 138 ° C .; hereinafter referred to as “COPP”] was used. As the resin for the resin layer (A2), ethylene- (meth) methyl acrylate copolymer (density: 0.940 g / cm ³ , MA content 18%; hereinafter referred to as “MA1”) was used. Each of these resins is supplied to an extruder for a resin layer (A1) (caliber 50 mm) and an extruder for a resin layer (A2) (caliber 50 mm) and melted at 200 to 250 ° C. Co-extruded multilayer film manufacturing apparatus (feed block and T-die temperature: 250 ° C.) having T die / chill roll method and co-melt extrusion are carried out, and the layer structure of the film is (A1) / (A2) A two-layered coextruded multilayer film having a thickness of 96 μm / 24 μm (total 120 μm) was obtained. The surface of the (A2) layer of the support was subjected to corona discharge treatment so that the wetting tension was 40 mN / m, and then the ink receiving agent (b-1) obtained in Preparation Example 1 was applied to prepare an inkjet recording medium. Produced. After printing on the receiving layer (B) of the obtained ink jet recording medium with an ink jet printer, an ester adhesive “LX500” manufactured by DIC Corporation is applied to the printed surface so that the thickness becomes 2 μm. And the 12-micrometer-thick Toyobo Co., Ltd. stretched polyester film (PET) was laminated, and the inkjet printed material of Example 1 was produced.

Example 2
An ink-jet printed material was produced in the same manner as in Example 1 except that the thickness of each layer of the layer structure (A1) / (A2) of the film of Example 1 was 56 μm / 14 μm (total 70 μm).

Example 3
An ink jet printed matter was produced in the same manner as in Example 1 except that the thickness of each layer of the layer constitution (A1) / (A2) of the film of Example 1 was 24 μm / 6 μm (total 30 μm).

Example 4
An inkjet printed material was produced in the same manner as in Example 1 except that the ink receiving agent (b-1) in Example 1 was changed to the ink receiving agent (b-2) obtained in Preparation Example 2.

Example 5
The acid-modified olefin resin of the resin layer (A2) of Example 1 was replaced with an ethylene-methyl acrylate copolymer (MA content 12%, density: 0.933 g / cm ³ ; hereinafter referred to as “MA2”). An ink-jet printed material was produced in the same manner as in Example 1 except that.

Example 6
The acid-modified olefin resin of the resin layer (A2) of Example 1 is an ethylene-methyl acrylate-maleic anhydride copolymer [density: 1.00 g / cm ³ , copolymer content: 15%; hereinafter referred to as “MA3”. An inkjet printed material was produced in the same manner as in Example 1 except that the description was replaced.

Example 7
An inkjet printed material was produced in the same manner as in Example 1 except that the resin MA1 for the resin layer (A2) of Example 1 was replaced with a blend of 50% and COPP 50%.

Example 8
An ink jet print was produced in the same manner as in Example 1 except that the resin MA1 for the resin layer (A2) of Example 1 was replaced with a blend of 20% and COPP of 80%.

Example 9
COPP of the resin layer (A1) of Example 7 was made of high-density polyethylene [density: 0.963 g / cm ³ , MFR: 7 g / 10 min (190 ° C., 21.18 N), melting point 130 ° C .; hereinafter referred to as “HDPE”. An ink-jet printed matter was produced in the same manner as in Example 7 except that the description was replaced.

Example 10
COPP of the resin layer (A1) of Example 7 was changed to medium density polyethylene [density: 0.934 g / cm ³ , MFR: 5.3 g / 10 min (190 ° C., 21.18 N), melting point 119 ° C .; Inkjet printed matter was produced in the same manner as in Example 7 except that the above was replaced.

Example 11
Example 1 except that the acrylic acid-modified resin of Example 1 was replaced with an ethylene- (meth) acrylic acid copolymer [density: 0.940 g / cm ³ , acid modification rate 12%; hereinafter referred to as “MA4”] In the same manner as in Example 1, an inkjet printed material was produced.

Example 12
An ink jet print was produced in the same manner as in Example 1 except that the thickness of each layer of the layer structure (A1) / (A2) of Example 1 was 114 μm / 6 μm (total 120 μm).

Example 13
An ink jet printed matter was produced in the same manner as in Example 1 except that the thickness of each layer of the layer structure (A1) / (A2) of the film of Example 1 was 90 μm / 30 μm (total 120 μm).

Example 14
An inkjet printed material was produced in the same manner as in Example 1 except that the stretched polyester film for overcoat treatment of Example 1 was a stretched nylon film (Ny) manufactured by Toyobo Co., Ltd.

Example 15
An inkjet printed material was produced in the same manner as in Example 1 except that the stretched polyester film for overcoat treatment in Example 1 was a stretched polypropylene film (PP) manufactured by Toyobo Co., Ltd.

Comparative Example 1
An inkjet printed material was produced in the same manner as in Example 15 except that the acid-modified olefin resin in the resin layer (A2) of Example 15 was replaced with COPP.

Comparative Example 2
Replacing COPP in resin layer (A1) of Comparative Example 1 with linear low density polyethylene [MFR: 4.0 g / 10 min (190 ° C., 21.18 N), melting point 105 ° C .; hereinafter referred to as “LLDPE”] An ink jet printed material was prepared in the same manner as in Comparative Example 1 except that the ink receiving agent (b-1) was changed to the ink receiving agent (b-2) obtained in Preparation Example 2.

Comparative Example 3
An inkjet printed material was produced in the same manner as in Example 1 except that the acid-modified olefin resin in the resin layer (A2) of Example 1 was replaced with HDPE.

Claims (13)

A layer (A1) comprising a polyolefin resin (a1) as a main component and a layer (A2) containing an acid-modified olefin resin (a2) are laminated such that the layer (A1) and the layer (A2) are adjacent to each other. formed by co-extrusion lamination molding method that is, the ink-receiving layer (B), the ink-jet printing on (A1) / (A2) / a layer of an inkjet recording medium formed by laminating in this order (B) (B) And performing an overcoat treatment on the printed surface. The method for producing an inkjet printed matter according to claim 1, wherein the polyolefin resin (a1) has a melting point of 110 ° C. or higher. The method for producing an ink-jet printed matter according to claim 1 or 2, wherein the acid-modified olefin resin (a2) has a modification rate of 3 to 40%. The method for producing an inkjet printed matter according to any one of claims 1 to 3, wherein the layer (A2) further contains a polyolefin-based resin. The ink-jet printed matter according to any one of claims 1 to 4, wherein the acid-modified olefin resin (a2) is contained in 20 parts by mass or more in 100 parts by mass of the resin component forming the layer (A2). Production method. The method for producing an inkjet printed matter according to any one of claims 1 to 5, wherein the ink receiving agent (b) contains a polyurethane resin (b1). The method for producing an inkjet printed matter according to claim 1, wherein the overcoat treatment is performed by laminating a resin film via an adhesive. The method for producing an inkjet printed matter according to claim 7, wherein the resin film is a stretched polypropylene film, a stretched nylon film, or a stretched polyester film. It is obtained by the manufacturing method according to any one of claims 1 to 8,
The layer (A1) containing the polyolefin resin (a1) as a main component, the layer (A2) containing the acid-modified olefin resin (a2), and the ink receiving layer (B) are (A1) / (A2). An inkjet printed matter, wherein inkjet printing is performed on the layer (B) of the inkjet recording medium laminated in the order of / (B), and further has an overcoat layer (C) on the printing surface. The inkjet printed matter according to claim 9, wherein the ratio of the layer (A2) to the total thickness of the layer (A1) and the layer (A2) is 5 to 40%. A packaging material using the inkjet printed matter according to any one of claims 9 to 10 . Packaging material according to claim 1 1, wherein one using the ink-jet prints alone. The inkjet print layer (A1) and in which is bag-making in the inner surface claim 1 1 or 1 2 Packaging material according.