JP5569659B1 - Laminated body and packaging material using the same - Google Patents

Abstract

  It has good adhesiveness with paper, is a hand-cut packaging material that can be easily opened by tearing by hand without the need for special processing, has little change in physical properties due to humidity, does not cause curling, and is dimensionally stable Provided are a laminate of a multilayer film and a paper base material, and a packaging material using the same, which can be suitably used as a packaging material having excellent properties and good laminating, printing, and packaging machine suitability. Specifically, a resin layer (A1) mainly composed of a cyclic olefin resin having a Tg of 130 ° C. or higher, a resin layer (B1) mainly composed of an olefin resin not containing a cyclic structure, and a cyclic olefin resin mainly. The resin layer (A1) of the multilayer film (I) having a multilayer structure in which the resin layer (A2) as a component is laminated in the order of (A1) / (B1) / (A2), and a paper substrate (II) And a laminated body characterized by being heat-sealed.

Description

  The present invention relates to a laminate comprising a paper base material that can be suitably used as a packaging material for pharmaceuticals, foods, industrial parts, cosmetics, sanitary products, miscellaneous goods, etc. The present invention relates to a laminate obtained by heat-sealing a multilayer film and a paper base material, which is good and has good openability, printability, laminateability, moisture resistance, packaging machineability, curl resistance and the like.

  Conventionally, bags made of a laminate of cellophane / polyethylene, cellophane / aluminum foil / polyethylene, etc. have been put to practical use as packaging materials with good hand tearability that can be easily opened by tearing with hands that do not require special processing. However, cellophane is hygroscopic, so the physical properties change due to humidity is large, dimensional stability is inferior, curling, blocking, etc. are suitable for laminating, printing, bag making, packaging machinery, etc. There was a problem.

  Furthermore, instead of bottles, outer boxes, and exterior films that describe medicinal ingredients, food ingredients, and methods of use, a part of a bag made of a laminate of cellophane / polyethylene, cellophane / aluminum foil / polyethylene, etc. is attached to the exterior paper. Simple packaging is used. In a form in which a packaging bag is formed in units of several or several tablets and sold separately, there is no space for describing the above-mentioned medicinal ingredients, food ingredients, usage methods, etc., and therefore an outer paper is essential.

  The cellophane and paper may be bonded to each other depending on whether an adhesive or sealant is applied or by thermal fusion, but thermal fusion is often used from the viewpoint of cost and environmental friendliness. However, since cellophane has heat resistance, high-temperature heating is necessary, adhesion to paper by heat melting is very difficult, and strength is weak. Further, in order to increase the strength, high heat and high pressure are required as sealing conditions. As a result, the fused portion is dirty, looks bad, causes a reduction in commercial value, and improvement is required.

  Polyester films have been proposed as an alternative to cellophane (see, for example, Patent Document 1). However, since the initial tear strength is high, special processing such as cutting of V notches and fine continuous holes is essential. . A packaging bag made of a syndiotactic polystyrene resin layer has also been proposed (see, for example, Patent Document 2). However, polystyrene is generally poor in moisture resistance, and packaging of contents with high hygroscopicity such as powders and tablets causes discoloration, deterioration of contents components, and the like, so that the storage period is limited. Furthermore, like cellophane, it was a material with very poor adhesion to paper.

  Moreover, in order to adhere a paper base material and the multilayer film used as a sealant, a method of providing an intermediate layer made of polyethylene resin without using an adhesive is provided (for example, see Patent Document 3). . In this method, the sealant film and the paper base material can be bonded without having an adhesive application step, and the adhesive strength with the paper base material can be maintained even when the fusing temperature is relatively low. However, it is known that the surface of a resin layer made of a polyethylene resin is generally not printable, and the printed surface is often peeled off over time, which is not suitable as a packaging material. Moreover, if it is stored in the state before printing, it becomes a cause of blocking. In addition, when laminated with a paper base material, the paper base material's easy-opening properties (easy tearing and straight-line cutting properties) are hindered, resulting in the need to form notches for opening and the like. It is not a thing with.

JP 2001-233374 A JP 2002-240209 A JP 2012-250488 A

  The present invention has been made in view of the above problems, and is a packaging material that has good adhesiveness to paper and can be easily opened by tearing by hand without requiring special processing. A multilayer film and a paper base material that can be suitably used as a packaging material that has little change in physical properties due to humidity, no curling, excellent dimensional stability, and good laminating, printing, and packaging machine suitability. It is providing the laminated body of this, and a packaging material using the same.

  As a result of earnest research to solve the above-mentioned problems, the present inventors have identified a cyclic olefin resin (a resin layer mainly composed of a cyclic olefin resin and a resin layer mainly composed of an olefin resin other than the cyclic olefin. The present inventors have found that the above-mentioned problems can be solved by using a multilayer film laminated so as to have a configuration, and have completed the present invention.

  That is, the present invention provides a resin layer (A1) mainly composed of a cyclic olefin resin (a1) having a glass transition temperature Tg of 130 ° C. or higher, and a resin mainly composed of an olefin resin (b1) not containing a cyclic structure. A multilayer film (I) having a multilayer structure in which a layer (B1) and a resin layer (A2) mainly composed of a cyclic olefin resin (a2) are laminated in the order of (A1) / (B1) / (A2) A laminate obtained by thermally fusing the resin layer (A1) and the paper substrate (II), and a packaging material using the laminate are provided.

  The laminate of the present invention can be easily opened by tearing by hand without performing special processing, and can provide a packaging material with good hand cutting properties. In addition, heat sealing (heat sealing) between the resin layer (A1) and paper is possible. Furthermore, since the multilayer film used for the laminate does not change in physical properties due to humidity, curling can be suppressed, dimensional stability is excellent, and blocking is difficult to occur. From these things, it is excellent in laminating, printing, and packaging machine suitability, and content deterioration due to moisture absorption can be suppressed. Further, it has an appropriate heat seal strength and can be suitably used for pharmaceuticals, foods, industrial materials and the like.

  The multilayer film (I) used in the present invention comprises a resin layer (A1) mainly composed of a cyclic olefin resin (a1) having a glass transition temperature Tg of 130 ° C. or higher, and an olefin resin (b1) not containing a cyclic structure. A multilayer structure in which a resin layer (B1) having a main component and a resin layer (A2) having a cyclic olefin resin (a2) as a main component are laminated in the order of (A1) / (B1) / (A2). It is essential to have other layers, and other layers may be further laminated on the resin layer (A2). In the present application, “main component” means that the specific resin is contained in an amount of 50% by mass or more with respect to the total mass of the resin component used for forming the resin layer. Means to contain at 60 mass% or more.

  In the case of using the multilayer film (I) formed with the multilayer structure of (A1) / (B1) / (A2), the resin used for the resin layers (A1) and (A2) on both surfaces is described later. The cyclic olefin-based resin may be a main component, and both layers may be made of the same material or different resin species. Moreover, the same kind of resin in which only the glass transition temperature is different may be used. Hereinafter, the cyclic olefin-based resins (a1) and (a2) may be described without distinction.

  Examples of the cyclic olefin-based resin that is the main component of the resin layers (A1) and (A2) in the present invention include norbornene-based polymers, vinyl alicyclic hydrocarbon polymers, and cyclic conjugated diene polymers. Among these, norbornene-based polymers are preferable. The norbornene-based polymer includes a ring-opening polymer of a norbornene-based monomer (hereinafter referred to as “COP”), a norbornene-based copolymer obtained by copolymerizing a norbornene-based monomer and an olefin such as ethylene (hereinafter, referred to as “COP”). , “COC”). Furthermore, COP and COC hydrogenates are particularly preferred. The weight average molecular weight of the cyclic olefin resin is preferably 5,000 to 500,000, more preferably 7,000 to 300,000. The glass transition temperature Tg of the cyclic olefin-based resin can be easily adjusted depending on the type of monomer used, the type and ratio of other monomers used for copolymerization, the molecular weight, and the like.

  The norbornene monomer used as a raw material for the norbornene polymer is an alicyclic monomer having a norbornene ring. Examples of such norbornene-based monomers include norbornene, tetracyclododecene, ethylidene norbornene, vinyl norbornene, ethylidetetracyclododecene, dicyclopentadiene, dimethanotetrahydrofluorene, phenyl norbornene, methoxycarbonyl norbornene, methoxy And carbonyltetracyclododecene. These norbornene monomers may be used alone or in combination of two or more.

  The norbornene-based copolymer is a copolymer of the norbornene-based monomer and an olefin copolymerizable with the norbornene-based monomer, and examples of such olefin include the number of carbon atoms such as ethylene, propylene, and 1-butene. Examples thereof include olefins having 2 to 20; cycloolefins such as cyclobutene, cyclopentene, and cyclohexene; and non-conjugated dienes such as 1,4-hexadiene. These olefins can be used alone or in combination of two or more.

  Further, the glass transition temperature Tg of the cyclic olefin-based resin (a1) needs to maintain the viewpoint and rigidity for heat-sealing the resin layer (A1) of the resulting multilayer film (I) and the paper substrate, In addition, from the viewpoint of preventing blocking during storage as the multilayer film (I), it is essential that the temperature is 130 ° C. or higher, and the multilayer film (I) can be produced by the coextrusion lamination method, and an industrial raw material. From the viewpoint of availability, Tg is preferably 200 ° C. or lower. The temperature is particularly preferably 130 ° C to 180 ° C. As such a cyclic olefin resin having Tg, the content ratio of the norbornene monomer is preferably in the range of 40 to 90% by weight, more preferably 50 to 90% by weight, still more preferably 60 to 85%. % By weight. When the content ratio is within this range, the heat resistance, rigidity, hand cutting property, moisture resistance, and processing stability are improved. In addition, the glass transition temperature Tg in this invention is a value obtained by measuring by DSC.

  Further, when the bag is made and filled with the contents, the inner layer is sealed with the resin layer (A1) facing outside. Considering packaging suitability, the resin layer (A1) needs to have heat resistance. Therefore, it is desirable to use a norbornene polymer in which the Tg of the cyclic olefin resin (a1) used for the resin layer (A1) is 150 ° C. or higher. .

  On the other hand, norbornene copolymers with a high glass transition temperature Tg have low tensile strength, and are extremely easy to break and tear easily. It is also possible to blend a low Tg product with a glass transition temperature of less than 100 ° C.

  If the rigidity is too high and there is a problem such as easy tearing or tearing due to a drop during transportation, or if a temperature difference between the front and back sides is to be given in consideration of packaging suitability, a norbornene-based copolymer with a Tg of less than 100 ° C By blending the coalescence, the falling bag strength and heat sealability can be improved. It is also effective to blend a polyolefin resin, an elastomer resin, or the like, such as a polypropylene resin or a polyethylene resin that is compatible with COC and does not contain a cyclic structure. Further, as a means for solving the above problem, as the cyclic olefin resin (a1) used for the resin layer (A1) which is the outermost surface, the cyclic olefin resin (a1) having a Tg of 130 ° C. or more as described above is used. A2) is a low-Tg resin when a cyclic olefin-based resin having a Tg of 100 ° C. or less is used alone or when a cyclic olefin-based resin having a Tg of 100 ° C. or more and a resin having a Tg of 100 ° C. or less are mixed. It is preferable to use the compound in an increased amount. Furthermore, the multilayer film (I) having a multilayer structure in which another resin layer is further laminated as described later on the resin layer (A2) is also effective in controlling the drop strength.

  As a commercial product that can be used as the cyclic olefin-based resin, examples of the ring-opening polymer (COP) of the norbornene-based monomer include “ZEONOR” manufactured by Nippon Zeon Co., Ltd. Examples of the coalescence (COC) include “Appel” manufactured by Mitsui Chemicals, Inc. and “TOPAS” manufactured by Polyplastics.

  The surface of the resin layer containing the cyclic olefin resin as a main component is excellent in surface gloss, and can maintain high quality as a packaging material. Moreover, since transparency is also favorable, it can be used as a packaging material having contents visibility.

Examples of the olefin resin (b1) that does not include a cyclic structure, which is the main component of the resin layer (B1) in the present invention, include various ethylene resins and propylene resins, and the resin layer (A1) and the resin layer. from adhesion and hand cutting property of the control of the cycloolefin resin used as a main component of (A2), the density of the olefin resin (b1) is 0.88 g / cm ² or more 0.940 g / cm ² less than A propylene-α-olefin random copolymer polymerized using an ethylene-based resin and / or a metallocene catalyst is preferred.

  Examples of the ethylene resin include polyethylene resins such as very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), and low density polyethylene (LDPE), ethylene-vinyl acetate copolymer (EVA), and ethylene-methyl. Methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), Ethylene copolymers such as ethylene-acrylic acid copolymer (EAA) and ethylene-methacrylic acid copolymer (EMAA); further, ionomer of ethylene-acrylic acid copolymer, ionomer of ethylene-methacrylic acid copolymer Used alone or in combination of two or more. And it may be. Among these, VLDPE, LDPE, and LLDPE are preferable because of a good balance between sealing properties and hand cutting properties.

  The LDPE may be a branched low density polyethylene obtained by a high pressure radical polymerization method, and is preferably a branched low density polyethylene obtained by homopolymerizing ethylene by a high pressure radical polymerization method.

  As LLDPE, an ethylene monomer is the main component by a low-pressure radical polymerization method using a single site catalyst, and an α-olefin such as butene-1, hexene-1, octene-1, 4-methylpentene is used as a comonomer. Are copolymerized. As a comonomer content rate in LLDPE, it is preferable that it is the range of 0.5-20 mol%, and it is more preferable that it is the range of 1-18 mol%.

  Examples of the single-site catalyst include various single-site catalysts such as metallocene catalyst systems such as combinations of metallocene compounds of Group IV or V transition metals and organoaluminum compounds and / or ionic compounds. In addition, the single-site catalyst has a uniform active site, so the molecular weight distribution of the resulting resin is sharper than a multi-site catalyst with a non-uniform active site. This is preferable because a resin having physical properties excellent in stability of sealing strength and anti-blocking property can be obtained.

As described above, the density of the ethylene-based resin is preferably 0.88 to 0.94 g / cm ³ . If the density is within this range, it has moderate rigidity, excellent mechanical strength such as heat seal strength and pinhole resistance, and film film formability and extrusion suitability are improved. Moreover, it is preferable that melting | fusing point is lower than Tg of the said cyclic olefin resin (a1), Although the range of a preferable melting | fusing point is determined by the cyclic olefin resin to be used, Generally 60-130 It is preferable that it is the range of degreeC, and 70-120 degreeC is more preferable. If melting | fusing point is this range, processing stability and coextrusion workability with cyclic olefin resin will improve. The MFR (190 ° C., 21.18N) of the ethylene-based resin is preferably 2 to 20 g / 10 minutes, and more preferably 3 to 10 g / 10 minutes. When the MFR is within this range, the extrusion moldability of the film is improved.

  Since such an ethylene-based resin has good compatibility with the cyclic olefin-based resin, it is possible to maintain transparency when laminated. In addition, without using an adhesive resin, etc., it can retain the interlayer adhesion strength of the resin layer (A1), resin layer (B1), and resin layer (A2), and has flexibility, so it has pinhole resistance Will also be good. Furthermore, when improving pinhole resistance, it is preferable to use VLDPE or LLDPE.

  Examples of the propylene resin include propylene homopolymer, propylene / α-olefin random copolymer, such as propylene-ethylene copolymer, propylene-butene-1 copolymer, propylene-ethylene-butene-1 copolymer. Examples include coalesced metallocene catalyst polypropylene. These may be used alone or in combination. Desirably, it is a propylene-α-olefin random copolymer, and a propylene / α-olefin random copolymer polymerized using a metallocene catalyst as described above is particularly preferable. When these propylene-based resins are used as the resin layer (B1), the heat resistance of the film is improved and the softening temperature can be increased, so that boiling at 100 ° C. or lower, hot filling, or 100 ° C. or higher is achieved. It can also be used as a packaging material having excellent steam / high pressure heat sterilization characteristics such as retort sterilization.

  These propylene resins preferably have an MFR (230 ° C.) of 0.5 to 30.0 g / 10 minutes and a melting point of 110 to 165 ° C., more preferably an MFR (230 ° C.) of 2 0.0-15.0 g / 10 min, melting point is 115-162 ° C. If MFR and melting | fusing point are this range, there will be little shrinkage | contraction of the film at the time of heat sealing, and also the film-forming property of a film will improve. Of course, the melting point is selected in relation to the glass transition temperature Tg of the cyclic olefin resin, as described for the ethylene resin.

  In the multilayer film (I) used in the present invention, the resin layer (A1), the resin layer (B1), and the resin layer (A2) are in the order of (A1) / (B1) / (A2). It has a multi-layer structure laminated on each other. That is, by sandwiching a resin layer mainly composed of an olefin resin between resin layers mainly composed of a cyclic olefin resin, a film having both hand cutting properties, moisture resistance and suitability for packaging machinery is obtained.

  In the three-layer multilayer film (I) having the multilayer structure of (A1) / (B1) / (A2), the film has a higher level of rigidity, hand cutting property and moisture resistance, and also has packaging machine characteristics. From the viewpoint of making it excellent, the thickness of the resin layer (B1) is preferably 30 to 80% of the total thickness of the multilayer film (I), and is laminated so as to be 40 to 70%. Is more preferable.

  When the multilayer film (I) having only the multilayer structure (A1) / (B1) / (A2) is used as the laminate of the present invention, particularly when it is heat-sealed to form a bag or the like, heat-sealing In order to prevent sticking of the resin to the seal bar at the time, it is preferable that the Tg of the cyclic olefin resin used for the resin layer (A1) and the resin layer (A2) is different. Specifically, the cyclic olefin resin used for the heat-sealing resin layer (A2) is a low Tg product, and the cyclic olefin resin used for the outermost resin layer (A1) is a high Tg product, Good suitability for packaging machines such as bag making and filling packaging.

  As described above, in addition to selecting and using Tg of the cyclic olefin resin used for the resin layer (A1) and the resin layer (A2), other resin layers can be laminated on the resin layer (A2). , Bag making and the like can be facilitated. In particular, a resin layer (B2) similar to the resin layer (B1) described above, that is, a resin layer (B2) mainly composed of an olefin resin (b2) not including a cyclic structure is laminated on the resin layer (A2). Therefore, it is possible to improve the heat sealability. At this time, as the olefin resin used for the resin layer (B2) to be laminated on the resin layer (A2), any of those described for the resin layer (B1) can be preferably used, and the preferred resin types are the same. It is. The resin type used for the resin layer (B1) disposed between the resin layer (A1) and the resin layer (A2) is the same as the resin type used for the resin layer (B2) laminated on the resin layer (A2). It may be different or different.

  A four-layer multilayer film (I) having the structure of (A1) / (B1) / (A2) / (B2), which has a higher level of film rigidity, hand cutting and moisture resistance, and a packaging machine From the viewpoint of excellent properties, the total thickness of the resin layer (B1) and the resin layer (B2) is preferably 40 to 95% of the total thickness of the multilayer structure, It is more preferable to laminate so that it may become%.

  Each of the resin layers (A1), (B1), (A2), and (B2) laminated as necessary includes an antifogging agent, an antistatic agent, a thermal stabilizer, a nucleating agent, an antioxidant, and a lubricant. In addition, components such as an anti-blocking agent, a release agent, an ultraviolet absorber and a colorant can be added within a range not impairing the object of the present invention. In particular, in order to impart processing suitability during film forming and packaging suitability of the filling machine, the outermost resin layer (A1) and the outermost resin layer (A2) in the case of a multilayer film having a three-layer structure, a four-layer structure The friction coefficient of the outermost resin layer (B2) in the case of the multilayer film is preferably 1.5 or less, and more preferably 1.0 or less. Therefore, the resin layer corresponding to the surface layer of the multilayer film (I) It is preferable to add a lubricant, an antiblocking agent and an antistatic agent as appropriate.

  Furthermore, the multilayer film (I) used in the present invention preferably has a film thickness of 15 to 100 μm, more preferably 20 to 90 μm. If the thickness of the film is within this range, stable hand cutting properties, laminating suitability, packaging machine suitability, excellent moisture resistance, heat sealability, and the like are easily obtained.

  Further, in the multilayer film (I) used in the present invention, the surface (one side and / or both sides) of the surface resin layer is treated so that the surface tension of the surface is 40 dyne / cm or more, preferably 42 dyne / cm or more. preferable. Examples of such treatment methods include corona treatment, plasma treatment, chromic acid treatment, flame treatment, hot air treatment, surface oxidation treatment such as ozone / ultraviolet treatment, and surface unevenness treatment such as sandblasting. Corona treatment is preferable. By performing such surface treatment, when the post-process such as printing or aluminum vapor deposition is performed on the multilayer film (I), the coating property of ink or adhesive is improved, and ink, aluminum, anchor coating agent, etc. It is easy to avoid problems such as ink or vapor deposition aluminum falling off or delamination. In particular, the resin layer containing a cyclic olefin-based resin is less likely to deteriorate with the lapse of time in corona treatment, and has good printability on the surface of the resin layer (A2) in the case of a resin film (A1) or a multilayer film having a three-layer structure. In addition, aluminum deposition on the resin layer (A2), application of an anchor coating agent, and the like are also good.

  Although it does not specifically limit as a manufacturing method of multilayer film (I) used by this invention, For example, resin layer (A1), resin layer (B1), resin layer (A2), resin layer (B2) laminated | stacked as needed (A1) / (B1) / (A2), or (A1) in a molten state by a method such as a coextrusion multilayer die method or a feed block method. ) / (B1) / (A2) / (B2), and then co-extrusion method in which the film is formed into a film by inflation or T-die / chill roll method. This coextrusion method is preferable because the thickness ratio of each layer can be adjusted relatively freely, and a multilayer film excellent in hygiene and cost performance can be obtained. Further, when the cyclic olefin resin used in the present invention and the ethylene resin are used as the resin layer (B1) and the resin layer (B2), the difference between the melting point and the Tg is large between them. Sometimes the film appearance deteriorates and it is difficult to form a uniform layer structure. In order to suppress such deterioration, a T-die / chill roll method that can perform melt extrusion at a relatively high temperature is preferable.

  Also, after laminating the multilayer structure (A1) / (B1) / (A2) using the coextrusion lamination method, the resin layer (B2) is laminated on the resin layer (A2) as described above. Applies various laminating methods such as dry lamination that is bonded by applying an adhesive, thermal lamination that is bonded by thermocompression of a heating roll, and extrusion lamination, and (A1) / (B1) / (A2) / It is also possible to form a multilayer structure (B2).

  Further, an aluminum foil or other thermoplastic resin film can be further laminated to provide further moisture resistance and barrier properties, or to provide light shielding properties for suppressing light deterioration of the contents. At this time, after the multilayer film (I) having the multilayer structure of (A1) / (B1) / (A2), (A1) / (B1) / (A2) / (B2) is manufactured, the adhesive is used. Applying various lamination methods such as dry laminating by coating, thermal laminating by thermo-compression of heating rolls and extrusion laminating, for example, (A1) / (B1) / (A2) / (aluminum foil) Or a thermoplastic resin film) / (B2), (A1) / (B1) / (A2) / (B2) / (aluminum foil or thermoplastic resin film) / (laminated layer having a multilayer structure) It is possible to form a body.

  In addition, when high heat seal strength, hot tackiness and high packaging speed are required, a special heat seal resin satisfying the above performance is further applied to the surface opposite to the resin layer (A1). Alternatively, a film having a special heat-sealable resin may be laminated to form a heat-seal layer, or a film having a special heat-sealable resin may be laminated by extrusion to form a heat-seal layer.

  Since the multilayer film (I) used in the present invention is obtained as a substantially unstretched multilayer film by the above-described production method, secondary molding such as deep drawing by vacuum molding and embossing is also possible.

  The multilayer film (I) used in the present invention uses a cyclic olefin resin as a component of the resin layer, thereby preventing adsorption of volatile components from the contents to the film (I) and providing a water vapor barrier property. Also have. From this, it can be suitably used as a packaging material used for foods, medicines, industrial parts, cosmetics, sanitary, miscellaneous goods, etc., and in particular, a packaging bag with good hand-cutability that can be easily opened by tearing by hand. Can be provided. Multilayer film (I) itself has little change in physical properties due to humidity, curling can be suppressed, dimensional stability is excellent, and blocking is difficult to occur, so it can be laminated and printed, and is suitable for packaging machinery. In addition, it can be suitably used for pharmaceuticals, foods, and the like from the viewpoint of excellent heat seal strength.

  The laminated body of the present invention forms a packaging bag in which the above-described multilayer film (I) is formed with the resin layer (A1) surface-treated as necessary as the outermost layer and the opposite resin layer as the inner side. It is preferable that the paper base (II) is heat-sealed to the resin layer (A1) which is the surface. For example, after cutting out the two sheets of the multilayer film (I) into a desired size of a packaging bag, overlapping them and heat-sealing three sides to form a bag, the contents from one side not heat-sealed Fill and heat seal. Furthermore, it is also possible to continuously and automatically form a packaging bag by sealing the end of a roll-shaped film in a cylindrical shape by an automatic packaging machine and then sealing the top and bottom. At this time, the paper substrate (II) is heat-sealed at the same or different part from the place to be heat-sealed. If the paper base material (II) is heat-sealed so as not to overlap the contents, it is possible to prevent the contents from being thermally deteriorated and poorly sealed. The paper base material (II) can be made into a packaging bag in which efficacy and the like are described by preliminarily describing matters relating to the contents by printing or hand-drawing. Alternatively, the resin layer (A1) that is the outermost surface of the multilayer film (I) is subjected to matters relating to the contents and various designs by printing, etc. By heat-sealing, a packaging material with a larger amount of information can be obtained.

  The paper substrate (II) used in the present invention is not particularly limited, and coated paper, art paper, high-quality paper, Kent paper, inkjet paper, rayon paper, synthetic paper, and the like can be used. An anti-blocking agent may be applied or embossed to improve printability and packaging suitability. The thickness is preferably in the range of 0.07 mm to 0.3 mm, and more preferably in the range of 0.09 to 0.2 mm from the viewpoint of good handling.

  Next, the present invention will be described in more detail with reference to examples and comparative examples.

As a resin for the resin layer (A1) on the surface of the reference example, a ring-opening polymer of a norbornene monomer [“Apel APL6015T” manufactured by Mitsui Chemicals, MFR: 10 g / 10 min (260 ° C., 21.18 N), glass transition temperature 145 ° C .; hereinafter referred to as “COC (1)”. ] Was used. As a resin for the opposite resin layer (A2), a ring-opening polymer of a norbornene-based monomer [“Apel APL8008T” manufactured by Mitsui Chemicals, Inc., MFR: 15 g / 10 min (260 ° C., 21.18 N), glass transition temperature: 70 ° C .; hereinafter referred to as “COC (4)”. ] 60 parts by mass and ultra-low density polyethylene [Density: 0.880 g / cm ³ , melting point 75 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N)]; hereinafter referred to as “VLLDPE”. 40 parts by weight of resin mixture was used. In addition, as the resin for the resin layer (B1), linear medium density polyethylene [density: 0.930 g / cm ³ , melting point 125 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N); " ] Was used. These resins were respectively supplied to the surface resin layer (A1) (A2) extruder (40 mm diameter) and the resin layer (B1) extruder (50 mm diameter) and melted at 200 to 270 ° C. The resin is supplied to a T-die / chill roll co-extrusion multi-layer film production apparatus (feed block and T-die temperature: 250 ° C.) having a feed block, and co-melt extrusion is performed. The layer structure of the film is (A1) / A coextruded multilayer film (X1) having a three-layer configuration of (B1) / (A2) and a thickness of each layer of 2 μm / 16 μm / 2 μm (total 20 μm) was obtained. The surface of the resin layer (A1) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

Example 1
As a resin for the resin layer (A1), a ring-opening polymer of a norbornene-based monomer [“TOPAS 6017” manufactured by Polyplastics Co., Ltd., MFR: 10 g / 10 minutes (260 ° C., 21.18 N), glass transition temperature: 170 ° C. Hereinafter referred to as “COC (2)”. ] 90 parts by mass and linear low density polyethylene [density: 0.900 g / cm ³ , melting point 85 ° C., MFR: 5 g / 10 min (190 ° C., 21.18 N); hereinafter referred to as “LLDPE”. 10 parts by mass of a resin mixture was used. As the resin for the resin layer (A2), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (4) was used. Moreover, LMDPE was used as resin for resin layers (B1). Co-extruded multilayer film in the same manner as in the reference example so that the layer structure of the film is (A1) / (B1) / (A2) and the thickness of each layer is 2 μm / 16 μm / 2 μm (total 20 μm) (X2) was obtained. The surfaces of the resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

Low density polyethylene (density: 0.920 g / cm ³ ) in which 2% of an antistatic agent (“Elester Master” manufactured by Kao) is blended on the resin layer (A2) of the coextruded multilayer film (X2) obtained above. , Melting point 115 ° C., MFR: 10 g / 10 min (190 ° C., 21.18 N); hereinafter referred to as “LDPE”. ] Was subjected to extrusion lamination of 20 μm by melt extrusion.

Example 2
LLDPE was used as the resin for the resin layer (B1). A coextruded multilayer film was produced in the same manner as in Example 1 so that the thickness of each layer of the film was 4 μm / 12 μm / 4 μm (total 20 μm), to obtain a coextruded multilayer film (X3). The surfaces of the resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

Propylene-α-olefin polymerized using a metallocene catalyst in which 0.2% of an antistatic agent is blended in the resin layer (A2) on the non-surface-treated side of the coextruded multilayer film (X3) obtained above. Random copolymer [density: 0.900 g / cm ³ , melting point 135 ° C., MFR: 4 g / 10 min (230 ° C., 21.18 N)]; hereinafter referred to as “MRCP”. And 20 μm of extrusion lamination was carried out by melt extrusion.

Example 3
As the resin for the resin layers (A1) and (A2), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (4) was used. Moreover, LMDPE was used as resin for the resin layer (B1). LLDPE was used as the resin for the resin layer (B2). The resin layer (B2) is supplied to an extruder (40 mm in diameter), and other resin layer resins are supplied in the same manner as in Example 1. The resin is melted at 200 to 270 ° C., and the molten resin is fed with a T having a feed block. Co-extrusion extrusion is carried out by supplying each to a die-chill roll co-extrusion multilayer film production apparatus (feed block and T-die temperature: 250 ° C.), and the layer structure of the film is (A1) / (B1) / (A2) A coextruded multilayer film (X4) having a four-layer structure of / (B2) and a thickness of each layer of 6 μm / 15 μm / 6 μm / 3 μm (total 30 μm) was obtained. The surface of the resin layer (A1) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

Example 4
A resin mixture of 70 parts by mass of COC (1) and 30 parts by mass of COC (4) was used as the resin for the resin layer (A1) on the surface, and MRCP was used as the resin for the resin layer (B1) of the inner layer. COC (4) was used for the inner resin layer (A2). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 2 μm / 16 μm / 2 μm (total 20 μm), to obtain a coextruded multilayer film (X5). The surface resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

The resin layer (A2) of the coextruded multilayer film (X5) obtained above was dry-laminated with an aluminum foil (thickness 12 μm) coated with a urethane-based adhesive to 3 g / m ² , and a laminated film (Y5 ) Further, a urethane adhesive was applied to the aluminum side of the Y5 film to 3 g / m ^2, and after drying, an LDPE film (melting point 110 ° C., manufactured by Phutamura Chemical Co., Ltd., hereinafter referred to as LLDPE-1) 20 μm was dry-laminated. (Z5) was obtained.

Example 5
COC (1) as the resin for the resin layer (A1) on the surface, ring-opening polymer of norbornene monomer as the resin for the resin layer (A2) on the inner layer [“APEL AP6013T” manufactured by Mitsui Chemicals, MFR: 15 g / 10 min (260 ° C., 21.18 N), glass transition temperature: 125 ° C .; hereinafter referred to as “COC (3)”. ] Was used. LLDPE was used as the resin for the resin layer (B1). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 2.5 μm / 20 μm / 2.5 μm (total 25 μm), to obtain a coextruded multilayer film (X6). The resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

The resin layer (A2) of the coextruded multilayer film (X6) obtained above was dry-laminated with an aluminum foil in the same manner as in Example 4 to obtain a laminated film (Y6).

Propylene-α-olefin random copolymer polymerized using a metallocene catalyst containing 0.2% of an antistatic agent on the aluminum foil surface of the laminated film (Y6) obtained above [Density: 0.900 g / cm ³ , melting point 135 ° C., MFR: 4 g / 10 min (230 ° C., 21.18 N); hereinafter referred to as “MRCP-1”. ) Was subjected to extrusion lamination of 20 μm by melt extrusion to obtain a laminated film (Z6).

Example 6
As the resin for the resin layers (A1) and (A2), a resin mixture of 50 parts by mass of COC (2) and 50 parts by mass of COC (4) was used. Moreover, LLDPE was used as resin for the resin layer (B). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 8 μm / 9 μm / 8 μm (total 25 μm), to obtain a coextruded multilayer film (X7). The resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 43 dyne / cm.

The resin layer (A2) of the coextruded multilayer film (X7) obtained above was dry laminated with an aluminum foil in the same manner as in Example 4 to obtain a laminated film (Y7).

Low density polyethylene (density: 0.920 g / cm ³ ) in which 2% of an antistatic agent (“Elester Master” manufactured by Kao) is blended in the resin layer (A2) of the coextruded multilayer film (Y2) obtained above. Melting point: 115 ° C., MFR: 10 g / 10 min (190 ° C., 21.18 N); hereinafter referred to as “LDPE-1”. Was laminated by melt extrusion to obtain a laminated film (Z7).

Example 7
As a resin for the resin layer (A1) on the surface, 70 parts by mass of COC (2) and high-density polyethylene [density: 0.960 g / cm ³ , melting point 128 ° C., MFR: 10 g / 10 min (190 ° C., 21.18 N) Hereinafter referred to as “HDPE”. 30 parts by mass of a resin mixture was used. Moreover, LLDPE was used as resin for the resin layer (B1). As the resin for the inner resin layer (A2), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (4) was used. A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 9 μm / 12 μm / 9 μm (total 30 μm), to obtain a coextruded multilayer film (X8). The surface resin layers (A1) and (A2) were subjected to corona treatment, and the surface tension by the wetting reagent was 41 dyne / cm.

  LDPE in which 0.2% of the antistatic agent was blended with the resin layer (A2) of the coextruded multilayer film (X8) obtained above was subjected to extrusion lamination of 20 μm by melt extrusion.

Example 8
As a resin for the resin layer (A1) on the surface, a resin mixture of 80 parts by mass of COC (1), 10 parts by mass of LLDPE and 10 parts by mass of HDPE was used. COC (4) was used as the resin for the inner resin layer (A2). LMDPE was used as the resin for the intermediate resin layer (B1). Furthermore, VLLDPE was used as the resin for the resin layer (B2) laminated on the inner resin layer (A2). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 18 μm / 40 μm / 18 μm / 14 μm (total 90 μm), to obtain a coextruded multilayer film (X9). The surface resin layer (A1) was subjected to corona treatment, and the surface tension by the wetting reagent was 45 dyne / cm.

Example 9
As the resin for the resin layers (A1) and (A2), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (4) was used. LMDPE was used as the resin for the intermediate resin layer (B1). VLLDPE was used as the resin for the outermost resin layer (B2). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 10 μm / 25 μm / 10 μm / 5 μm (total 50 μm), to obtain a coextruded multilayer film (X10). The surface resin layer (A1) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 dyne / cm.

Example 10
As the resin for the resin layers (A1) and (A2), a resin mixture of 50 parts by mass of COC (1) and 50 parts by mass of COC (4) was used. LMDPE was used as the resin for the intermediate resin layer (B1). LLDPE was used as the resin for the outermost resin layer (B2). A coextruded multilayer film was produced in the same manner as in the reference example so that the thickness of each layer of the film was 6 μm / 15 μm / 6 μm / 3 μm (total 30 μm), to obtain a coextruded multilayer film (X11). The surface resin layer (A1) was subjected to corona treatment, and the surface tension by the wetting reagent was 43 dyne / cm.

The resin layer (B2) of the coextruded multilayer film (X11) obtained above was dry-laminated with aluminum foil and LLDPE-1 in the same manner as in Example 4 to obtain a laminated film (Z6).

Comparative Example 1
COC (1) was used as the resin for the surface resin layer. As an intermediate layer resin, homopolypropylene [density: 0.900 g / cm ³ , melting point 160 ° C., MFR: 7 g / 10 min (230 ° C., 21.18 N); hereinafter referred to as “PP”. ] Was used. A coextruded multilayer film was produced in the same manner as in Example 1 so that the thickness of each layer of the film was 10 μm / 10 μm (total 20 μm), and a coextruded multilayer film was obtained. The surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

  LDPE blended with 0.2% of an antistatic agent as a heat-sealable resin in the intermediate resin layer of the coextruded multilayer film obtained above was subjected to extrusion lamination of 20 μm by melt extrusion.

Comparative Example 2
COC (3) was used as the resin for the surface resin layer. LMDPE was used as the intermediate layer resin. A coextruded multilayer film was produced in the same manner as in Example 1 so that the thickness of each layer of the film was 36 μm / 4 μm (total 40 μm), to obtain a coextruded multilayer film (Y2). The surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

Comparative Example 3
COC (3) was used as the resin for the surface resin layer. VLDPE was used as the intermediate layer resin. A coextruded multilayer film was produced in the same manner as in Example 1 so that the thickness of each layer of the film was 0.5 μm / 19 μm / 0.5 μm (total 20 μm), to obtain a coextruded multilayer film (Y2). The surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

Comparative Example 4
COC (1) was used as the resin for the surface resin layer. LMDPE was used as the intermediate layer resin. A coextruded multilayer film was produced in the same manner as in Example 2 so that the thickness of each layer of the film was 4 μm / 36 μm (total 40 μm), to obtain a coextruded multilayer film (Y2). The surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 40 dyne / cm.

Comparative Example 5
HDPE was used as the resin for the surface resin layer. LMDPE was used as the intermediate layer resin. A coextruded multilayer film was produced in the same manner as in Example 1 so that the thickness of each layer of the film was 4 μm / 100 μm (total 104 μm), to obtain a coextruded multilayer film (Y3). The surface resin layer was subjected to corona treatment, and the surface tension by the wetting reagent was 38 dyne / cm.

  MRCP containing 0.2% of an antistatic agent on the intermediate layer side of the coextruded multilayer film (Y3) obtained above was subjected to extrusion lamination of 20 μm by melt extrusion.

Comparative Example 6
LDPE blended with 0.2% of an antistatic agent as a heat-sealable resin on Cellophane (# 300) manufactured by Futamura Chemical Co., Ltd. was subjected to extrusion lamination of 20 μm by melt extrusion.

The following tests and evaluations were performed using the multilayer films obtained in the above Reference Examples , Examples 1 to 10 and Comparative Examples 1 to 6.

Whether the film before heat fusion with the paper base material obtained above is torn by hand in a state where two films are stacked without cutting into the film according to the following criteria. The tearability was evaluated. Evaluation was implemented with respect to the longitudinal direction (MD) and the width direction (TD), respectively.
○: Can be easily torn by hand.
X: What cannot be easily torn by hand.

Ink adhesion DIC Co., Ltd. surface printing ink: applied to the surface (surface of the resin layer (A1)) subjected to corona treatment so that the thickness of the coated film after drying is 2 μm using Ultima NT white And an evaluation film was obtained. After leaving at 40 ° C. for 24 hours, a cellophane tape (18 mm width) manufactured by Nichiban Co., Ltd. was applied to the ink coated surface in a length of 5 cm so as not to contain air bubbles, and a constant load was applied thereto with a 5 kg load roll. The ink adhesion was evaluated according to the following criteria for the peeled state when peeled at high speed by force.
○: The ink does not peel at all. Δ: The ink peels from the film surface, but the peeled area is less than 10%.
X: The ink peels in an area of 10% or more.

Packing machine suitability under high humidity The film before thermal fusion with the paper base material prepared in the examples and comparative examples is subjected to vertical pillow packaging at 33 ° C and 80% humidity under the following conditions using an automatic packaging machine. Done and made a bag.
Packaging machine: Rika Kaken Co., Ltd. Unipacker NUV472

Horizontal seal: speed 30 bags / min, vertical heat seal temperature 150 ° C, air gauge pressure 4kg / cm ² , resin layers that have not been surface-treated while changing from horizontal heat seal temperature 120 ° C to 160 ° C in increments of 10 ° C Sealed. 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 After film-making under the above conditions at 23 ° C., the film was naturally cooled, and then a test piece was cut into a strip of 15 mm width. 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.

Curl resistance The paper base material obtained above and the film before heat fusion were cut out 10 cm in length and width and stored for 24 hours at 40 ° C. and 90% humidity. The film was conditioned at 23 ° C. and 50% humidity for 1 hour, and the curled state of the film was observed. The film was spread on a flat surface and the height at which both end surfaces were raised was measured, and the curl resistance was evaluated according to the following criteria.
○: Less than 3 cm in height Δ: 3 cm or more in height ×: Both ends of the film overlap and become completely rounded

Adhesiveness with paper substrate Coated paper 0.1 mm was used as a paper substrate. The multilayer films obtained in the above Examples and Comparative Examples were sealed with a paper base material at a seal temperature of 230 ° C., a seal pressure of 0.4 MPa, and a seal time of 1 second. The seal shape was a two-wire seal with a width of 0.2 mm.

The film sealed 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 50 g / 15 mm width or more.
X: Heat seal strength is less than 50 g / 15 mm width.

  The results obtained above are shown in Tables 1-2.

Claims (14)

A resin layer (A1) mainly composed of a cyclic olefin resin (a1) having a glass transition temperature Tg of 130 ° C. or higher, a resin layer (B1) mainly composed of an olefin resin (b1) not containing a cyclic structure, The resin layer (A2) mainly composed of the olefin resin (a2) is laminated in the order of (A1) / (B1) / (A2),
Furthermore, the resin layer (A1) of the multilayer film (I) having a multilayer structure in which the resin layer (B2) mainly composed of the olefin resin (b2) not containing a cyclic structure is laminated on the resin layer (A2). And a paper base material (II) are heat-sealed. The laminate according to claim 1, wherein the cyclic olefin resins (a1) and (a2) are norbornene polymers. The resin constituting the resin layer (A1) does not contain a cyclic olefin resin (a1) having a glass transition temperature Tg of 130 ° C. or higher, a cyclic olefin resin having a glass transition temperature Tg of 100 ° C. or lower, or a cyclic structure. The laminate according to claim 1 or 2 , which is a mixture with an olefin resin. The olefin resin (b1), density of 0.88 g / cm ² or more 0.940 g / cm ² less than a ethylene-based resin laminate of any one of claims 1 to 3 of (b2). The laminate according to any one of claims 1 to 4, wherein the olefin resins (b1) and (b2) are propylene-α-olefin random copolymers polymerized using a metallocene catalyst. The laminate according to any one of claims 1 to 5 , wherein the multilayer film (I) is laminated by a coextrusion lamination method. The resin layer (B2) is laminated by an extrusion laminating method on the resin layer (A2) of the multilayer film (I) having a multilayer structure laminated in the order of (A1) / (B1) / (A2). The laminate according to claim 1. The total thickness of the resin layer (B1) and the resin layer (B2) in the multilayer structure of the resin layer (A1) / the resin layer (B1) / the resin layer (A2) / the resin layer (B2) is The laminate according to claim 1, which is 40 to 95% of the total thickness of the multilayer structure. The laminate according to any one of claims 1 to 8 , wherein the total thickness of the multilayer film (I) is in the range of 15 to 100 µm. A resin layer (A1) mainly composed of a cyclic olefin resin (a1) having a glass transition temperature Tg of 130 ° C. or higher, a resin layer (B1) mainly composed of an olefin resin (b1) not containing a cyclic structure, The resin layer (A2) mainly composed of the olefin resin (a2) is laminated in the order of (A1) / (B1) / (A2), and an aluminum foil is laminated on the resin layer (A2). A resin layer (A1) of a multilayer film having a multilayer structure in which a resin layer (B2) mainly composed of an olefin-based resin (b2) not containing a cyclic structure is laminated on an aluminum foil, and a paper substrate (II ) Are heat-sealed . Wherein after bag-making in the outermost layer of the multilayer film resin layer (I) (A1), claim is made by heat sealing the paper substrate (II) in the resin layer (A1) plane 1-9 The laminate according to any one of the above. The laminate according to claim 10, wherein the outermost layer of the resin layer (A1) of the multilayer film is made into a bag and then the paper substrate (II) is heat-sealed to the surface of the resin layer (A1). A packaging material comprising the laminate according to any one of claims 1 to 12 . Claim 1 3 packaging material according a food or pharmaceutical.